From: Kees van Reeuwijk <reeuwijk@few.vu.nl>
Date: Wed, 7 Apr 2010 11:25:51 +0000 (+0000)
Subject: Removed unused variables, added const where possible.
X-Git-Tag: v3.1.7~174
X-Git-Url: http://zhaoyanbai.com/repos/Bv9ARM.pdf?a=commitdiff_plain;h=94a81c840a1b902a372e7488581d253111d94ee3;p=minix.git

Removed unused variables, added const where possible.
---

diff --git a/boot/boot.c b/boot/boot.c
index 2f30fa172..56e2bd0a4 100644
--- a/boot/boot.c
+++ b/boot/boot.c
@@ -773,7 +773,7 @@ static environment **searchenv(const char *name)
 #define b_getenv(name)	(*searchenv(name))
 /* Return the environment *structure* belonging to name, or nil if not found. */
 
-char *b_value(char *name)
+char *b_value(const char *name)
 /* The value of a variable. */
 {
 	environment *e= b_getenv(name);
@@ -781,7 +781,7 @@ char *b_value(char *name)
 	return e == nil || !(e->flags & E_VAR) ? nil : e->value;
 }
 
-static char *b_body(char *name)
+static char *b_body(const char *name)
 /* The value of a function. */
 {
 	environment *e= b_getenv(name);
@@ -789,7 +789,8 @@ static char *b_body(char *name)
 	return e == nil || !(e->flags & E_FUNCTION) ? nil : e->value;
 }
 
-static int b_setenv(int flags, char *name, char *arg, char *value)
+static int b_setenv(int flags, const char *name, const char *arg,
+  const char *value)
 /* Change the value of an environment variable.  Returns the flags of the
  * variable if you are not allowed to change it, 0 otherwise.
  */
@@ -838,7 +839,7 @@ int b_setvar(int flags, char *name, char *value)
 	return r;
 }
 
-void b_unset(char *name)
+void b_unset(const char *name)
 /* Remove a variable from the environment.  A special variable is reset to
  * its default value.
  */
@@ -919,7 +920,7 @@ static void get_parameters(void)
 {
 	char params[SECTOR_SIZE + 1];
 	token **acmds;
-	int r, bus, processor;
+	int r, processor;
 	memory *mp;
 	static char bus_type[][4] = {
 		"xt", "at", "mca"
@@ -1116,7 +1117,6 @@ dev_t name2dev(char *name)
 {
 	dev_t dev;
 	ino_t ino;
-	int drive;
 	struct stat st;
 	char *n, *s;
 
diff --git a/boot/boot.h b/boot/boot.h
index 51ae27939..f73f19042 100644
--- a/boot/boot.h
+++ b/boot/boot.h
@@ -167,9 +167,9 @@ typedef struct environment {
 
 EXTERN environment *env;	/* Lists the environment. */
 
-char *b_value(char *name);	/* Get/set the value of a variable. */
+char *b_value(const char *name);	/* Get/set the value of a variable. */
 int b_setvar(int flags, char *name, char *value);
-void b_unset(char *name);
+void b_unset(const char *name);
 
 void parse_code(char *code);	/* Parse boot monitor commands. */
 
diff --git a/boot/installboot.c b/boot/installboot.c
index 29e53a3d4..5b334bf68 100644
--- a/boot/installboot.c
+++ b/boot/installboot.c
@@ -3,7 +3,6 @@
  *
  * Either make a device bootable or make an image from kernel, mm, fs, etc.
  */
-#define nil 0
 #define _POSIX_SOURCE	1
 #define _MINIX		1
 #include <stdio.h>
@@ -61,12 +60,12 @@ char *basename(char *name)
 	static char base[IM_NAME_MAX];
 	char *p, *bp= base;
 
-	if ((p= strchr(name, ':')) != nil) {
+	if ((p= strchr(name, ':')) != NULL) {
 		while (name <= p && bp < base + IM_NAME_MAX - 1)
 			*bp++ = *name++;
 	}
 	for (;;) {
-		if ((p= strrchr(name, '/')) == nil) { p= name; break; }
+		if ((p= strrchr(name, '/')) == NULL) { p= name; break; }
 		if (*++p != 0) break;
 		*--p= 0;
 	}
@@ -85,7 +84,7 @@ static void bread(FILE *f, char *name, void *buf, size_t len)
 	}
 }
 
-static void bwrite(FILE *f, char *name, const void *buf, size_t len)
+static void bwrite(FILE *f, const char *name, const void *buf, size_t len)
 {
 	if (len > 0 && fwrite(buf, len, 1, f) != 1) fatal(name);
 }
@@ -95,14 +94,14 @@ int making_image= 0;
 
 void read_header(int talk, char *proc, FILE *procf, struct image_header *ihdr)
 /* Read the a.out header of a program and check it.  If procf happens to be
- * nil then the header is already in *image_hdr and need only be checked.
+ * NULL then the header is already in *image_hdr and need only be checked.
  */
 {
 	int n, big= 0;
 	static int banner= 0;
 	struct exec *phdr= &ihdr->process;
 
-	if (procf == nil) {
+	if (procf == NULL) {
 		/* Header already present. */
 		n= phdr->a_hdrlen;
 	} else {
@@ -122,7 +121,7 @@ void read_header(int talk, char *proc, FILE *procf, struct image_header *ihdr)
 	}
 
 	/* Get the rest of the exec header. */
-	if (procf != nil) {
+	if (procf != NULL) {
 		bread(procf, proc, ((char *) phdr) + A_MINHDR,
 						phdr->a_hdrlen - A_MINHDR);
 	}
@@ -160,7 +159,7 @@ void read_header(int talk, char *proc, FILE *procf, struct image_header *ihdr)
 	}
 }
 
-void padimage(char *image, FILE *imagef, int n)
+void padimage(const char *image, FILE *imagef, int n)
 /* Add n zeros to image to pad it to a sector boundary. */
 {
 	while (n > 0) {
@@ -206,16 +205,16 @@ void make_image(char *image, char **procv)
 
 	making_image= 1;
 
-	if ((imagef= fopen(image, "w")) == nil) fatal(image);
+	if ((imagef= fopen(image, "w")) == NULL) fatal(image);
 
-	for (procn= 0; (proc= *procv++) != nil; procn++) {
+	for (procn= 0; (proc= *procv++) != NULL; procn++) {
 		/* Remove the label from the file name. */
-		if ((file= strchr(proc, ':')) != nil) file++; else file= proc;
+		if ((file= strchr(proc, ':')) != NULL) file++; else file= proc;
 
 		/* Real files please, may need to seek. */
 		if (stat(file, &st) < 0
 			|| (errno= EISDIR, !S_ISREG(st.st_mode))
-			|| (procf= fopen(file, "r")) == nil
+			|| (procf= fopen(file, "r")) == NULL
 		) fatal(proc);
 
 		/* Read a.out header. */
@@ -296,7 +295,7 @@ void extract_image(char *image)
 	/* Size of the image. */
 	len= S_ISREG(st.st_mode) ? st.st_size : -1;
 
-	if ((imagef= fopen(image, "r")) == nil) fatal(image);
+	if ((imagef= fopen(image, "r")) == NULL) fatal(image);
 
 	while (len != 0) {
 		/* Extract a program, first sector is an extended header. */
@@ -307,9 +306,9 @@ void extract_image(char *image)
 		phdr= ihdr.process;
 
 		/* Check header. */
-		read_header(1, ihdr.name, nil, &ihdr);
+		read_header(1, ihdr.name, NULL, &ihdr);
 
-		if ((procf= fopen(ihdr.name, "w")) == nil) fatal(ihdr.name);
+		if ((procf= fopen(ihdr.name, "w")) == NULL) fatal(ihdr.name);
 
 		if (phdr.a_flags & A_PAL) {
 			/* A page aligned process contains a header in text. */
@@ -333,8 +332,8 @@ void extract_image(char *image)
 	}
 }
 
-int rawfd;	/* File descriptor to open device. */
-char *rawdev;	/* Name of device. */
+static int rawfd;	/* File descriptor to open device. */
+static const char *rawdev;	/* Name of device. */
 
 void readblock(off_t blk, char *buf, int block_size)
 /* For rawfs, so that it can read blocks. */
@@ -378,7 +377,7 @@ int raw_install(char *file, off_t *start, off_t *len, int block_size)
 	devsize= -1;
 	if (ioctl(rawfd, DIOCGETP, &entry) == 0) devsize= cv64ul(entry.size);
 
-	if ((f= fopen(file, "r")) == nil) fatal(file);
+	if ((f= fopen(file, "r")) == NULL) fatal(file);
 
 	/* Copy sectors from file onto the boot device. */
 	sec= *start;
@@ -486,7 +485,7 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 		 */
 		if (stat(bootcode, &st) < 0) fatal(bootcode);
 
-		if ((bootf= fopen(bootcode, "r")) == nil) fatal(bootcode);
+		if ((bootf= fopen(bootcode, "r")) == NULL) fatal(bootcode);
 	} else {
 		/* Boot code is present in the file system. */
 		r_stat(ino, &st);
@@ -499,14 +498,14 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 			/* Must skip 16 bytes of 'boot' as that contains code. */
 			memcpy(&boothdr, buf + 16, sizeof(struct exec));
 		}
-		bootf= nil;
+		bootf= NULL;
 		dummy.process= boothdr;
 	}
 	/* See if it is an executable (read_header does the check). */
 	read_header(0, bootcode, bootf, &dummy);
 	boothdr= dummy.process;
 
-	if (bootf != nil) fclose(bootf);
+	if (bootf != NULL) fclose(bootf);
 
 	/* Get all the sector addresses of the secondary boot code. */
 	max_sector= (boothdr.a_hdrlen + boothdr.a_text
@@ -551,7 +550,7 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 	/* Get the boot block and patch the pieces in. */
 	readblock(BOOTBLOCK, buf, BOOT_BLOCK_SIZE);
 
-	if ((bootf= fopen(bootblock, "r")) == nil) fatal(bootblock);
+	if ((bootf= fopen(bootblock, "r")) == NULL) fatal(bootblock);
 
 	read_header(0, bootblock, bootf, &dummy);
 	boothdr= dummy.process;
@@ -596,7 +595,7 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 	 * necessary.
 	 */
 	for (parmp= buf + SECTOR_SIZE; parmp < buf + 2*SECTOR_SIZE; parmp++) {
-		if (*imagev != nil || (control(*parmp) && *parmp != '\n')) {
+		if (*imagev != NULL || (control(*parmp) && *parmp != '\n')) {
 			/* Param sector must be initialized. */
 			memset(buf + SECTOR_SIZE, '\n', SECTOR_SIZE);
 			break;
@@ -629,10 +628,10 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 		parmp+= strlen(parmp);
 	}
 
-	while ((labels= *imagev++) != nil) {
+	while ((labels= *imagev++) != NULL) {
 		/* Place each kernel image on the boot device. */
 
-		if ((image= strchr(labels, ':')) != nil)
+		if ((image= strchr(labels, ':')) != NULL)
 			*image++= 0;
 		else {
 			if (nolabel) {
@@ -642,23 +641,23 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 			}
 			nolabel= 1;
 			image= labels;
-			labels= nil;
+			labels= NULL;
 		}
 		len= 0;
 		if (!raw_install(image, &pos, &len, block_size)) exit(1);
 
-		if (labels == nil) {
+		if (labels == NULL) {
 			/* Let this image be the default. */
 			sprintf(parmp, "image=%ld:%ld\n", pos-len, len);
 			parmp+= strlen(parmp);
 		}
 
-		while (labels != nil) {
+		while (labels != NULL) {
 			/* Image is prefixed by a comma separated list of
 			 * labels.  Define functions to select label and image.
 			 */
 			label= labels;
-			if ((labels= strchr(labels, ',')) != nil) *labels++ = 0;
+			if ((labels= strchr(labels, ',')) != NULL) *labels++ = 0;
 
 			sprintf(parmp,
 		"%s(%c){label=%s;image=%ld:%ld;echo %s kernel selected;menu}\n",
@@ -685,7 +684,7 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 	}
 }
 
-static void install_master(char *device, char *masterboot, char **guide)
+static void install_master(const char *device, char *masterboot, char **guide)
 /* Booting a hard disk is a two stage process:  The master bootstrap in sector
  * 0 loads the bootstrap from sector 0 of the active partition which in turn
  * starts the operating system.  This code installs such a master bootstrap
@@ -702,7 +701,7 @@ static void install_master(char *device, char *masterboot, char **guide)
 	if ((rawfd= open(rawdev= device, O_RDWR)) < 0) fatal(device);
 
 	/* Open the master boot code. */
-	if ((masf= fopen(masterboot, "r")) == nil) fatal(masterboot);
+	if ((masf= fopen(masterboot, "r")) == NULL) fatal(masterboot);
 
 	/* See if the user is cloning a device. */
 	if (fstat(fileno(masf), &st) >=0 && S_ISBLK(st.st_mode))
@@ -725,7 +724,7 @@ static void install_master(char *device, char *masterboot, char **guide)
 	memset(buf, 0, PARTPOS);
 	(void) bread(masf, masterboot, buf, size);
 
-	if (guide[0] != nil) {
+	if (guide[0] != NULL) {
 		/* Fixate partition to boot. */
 		const char *keys= guide[0];
 		const char *logical= guide[1];
@@ -755,7 +754,7 @@ static void install_master(char *device, char *masterboot, char **guide)
 		size += i;
 		buf[size]= '\r';
 
-		if (logical != nil) {
+		if (logical != NULL) {
 			if ((logfd= open(logical, O_RDONLY)) < 0
 				|| ioctl(logfd, DIOCGETP, &geometry) < 0
 			) {
@@ -793,7 +792,7 @@ static void usage(void)
 	exit(1);
 }
 
-static int isoption(const char *option, char *test)
+static int isoption(const char *option, const char *test)
 /* Check if the option argument is equals "test".  Also accept -i as short
  * for -image, and the special case -x for -extract.
  */
diff --git a/boot/mkfile.c b/boot/mkfile.c
index 60c06228f..d9a130d54 100644
--- a/boot/mkfile.c
+++ b/boot/mkfile.c
@@ -72,7 +72,6 @@ char *strerror(int err)
 
 int main(int argc, char **argv)
 {
-	int i;
 	static char buf[512];
 	unsigned long size, mul;
 	off_t offset;
diff --git a/commands/ash/alias.c b/commands/ash/alias.c
index 5a8a3c1cf..9f197ed6e 100644
--- a/commands/ash/alias.c
+++ b/commands/ash/alias.c
@@ -55,13 +55,13 @@ __FBSDID("$FreeBSD: src/bin/sh/alias.c,v 1.18 2004/04/06 20:06:51 markm Exp $");
 
 STATIC struct alias *atab[ATABSIZE];
 
-STATIC void setalias(char *, char *);
-STATIC int unalias(char *);
+STATIC void setalias(const char *, const char *);
+STATIC int unalias(const char *);
 STATIC struct alias **hashalias(const char *);
 
 STATIC
 void
-setalias(char *name, char *val)
+setalias(const char *name, const char *val)
 {
 	struct alias *ap, **app;
 
@@ -114,7 +114,7 @@ setalias(char *name, char *val)
 }
 
 STATIC int
-unalias(char *name)
+unalias(const char *name)
 {
 	struct alias *ap, **app;
 
@@ -175,7 +175,7 @@ rmaliases(void)
 }
 
 struct alias *
-lookupalias(char *name, int check)
+lookupalias(const char *name, int check)
 {
 	struct alias *ap = *hashalias(name);
 
diff --git a/commands/ash/alias.h b/commands/ash/alias.h
index e541908f4..5b4fb8fae 100644
--- a/commands/ash/alias.h
+++ b/commands/ash/alias.h
@@ -42,7 +42,7 @@ struct alias {
 	int flag;
 };
 
-struct alias *lookupalias(char *, int);
+struct alias *lookupalias(const char *, int);
 int aliascmd(int, char **);
 int unaliascmd(int, char **);
 void rmaliases(void);
diff --git a/commands/ash/cd.c b/commands/ash/cd.c
index 055cb75a0..8513128ed 100644
--- a/commands/ash/cd.c
+++ b/commands/ash/cd.c
@@ -67,9 +67,9 @@ __FBSDID("$FreeBSD: src/bin/sh/cd.c,v 1.34 2004/04/06 20:06:51 markm Exp $");
 #include "show.h"
 #include "cd.h"
 
-STATIC int cdlogical(char *);
+STATIC int cdlogical(const char *);
 STATIC int cdphysical(const char *);
-STATIC int docd(char *, int, int);
+STATIC int docd(const char *, int, int);
 STATIC char *getcomponent(void);
 STATIC int updatepwd(const char *);
 
@@ -145,7 +145,7 @@ cdcmd(int argc, char **argv)
  * directory name if "print" is nonzero.
  */
 STATIC int
-docd(char *dest, int print, int phys)
+docd(const char *dest, int print, int phys)
 {
 
 	TRACE(("docd(\"%s\", %d, %d) called\n", dest, print, phys));
@@ -161,7 +161,7 @@ docd(char *dest, int print, int phys)
 }
 
 STATIC int
-cdlogical(char *dest)
+cdlogical(const char *dest)
 {
 	char *p;
 	char *q;
diff --git a/commands/ash/memalloc.c b/commands/ash/memalloc.c
index 8f567cce9..ab4900f46 100644
--- a/commands/ash/memalloc.c
+++ b/commands/ash/memalloc.c
@@ -83,7 +83,7 @@ ckrealloc(pointer p, int nbytes)
  */
 
 char *
-savestr(char *s)
+savestr(const char *s)
 {
 	char *p;
 
diff --git a/commands/ash/memalloc.h b/commands/ash/memalloc.h
index f3c9138f0..68b89a207 100644
--- a/commands/ash/memalloc.h
+++ b/commands/ash/memalloc.h
@@ -48,7 +48,7 @@ extern int herefd;
 
 pointer ckmalloc(int);
 pointer ckrealloc(pointer, int);
-char *savestr(char *);
+char *savestr(const char *);
 pointer stalloc(int);
 void stunalloc(pointer);
 void setstackmark(struct stackmark *);
diff --git a/commands/awk/lex.c b/commands/awk/lex.c
index 49d7c5ca7..a7e225d77 100644
--- a/commands/awk/lex.c
+++ b/commands/awk/lex.c
@@ -434,7 +434,7 @@ int string(void)
 }
 
 
-int binsearch(char *w, Keyword *kp, int n)
+int binsearch(const char *w, const Keyword *kp, int n)
 {
 	int cond, low, mid, high;
 
diff --git a/commands/elle/eecmds.c b/commands/elle/eecmds.c
index b92183f59..757d8bebb 100644
--- a/commands/elle/eecmds.c
+++ b/commands/elle/eecmds.c
@@ -217,7 +217,6 @@ register int c;
 set_profile(filename)
 char *filename;
 {	char pfile[200];
-	char psfile[200];
 	register int pfd, len;
 	chroff sbx_fdlen();
 	register char *profptr;
diff --git a/commands/elle/eedisp.c b/commands/elle/eedisp.c
index 3827bb71e..d1ceb3136 100644
--- a/commands/elle/eedisp.c
+++ b/commands/elle/eedisp.c
@@ -798,7 +798,7 @@ struct window *win;
 {	register int i, n;
 	register struct scr_line *s;
 	struct window *w;
-	int top, bot, dspf, num, isave, noicost, nodcost, iline, dline;
+	int top, bot, dspf, num, noicost, nodcost, iline, dline;
 #if FX_SOWIND
 	int oldso;
 #endif
@@ -1354,7 +1354,6 @@ struct scr_line *olds;
 {	register struct scr_line *s;
 	register int col, scrw;
 	char *cp;
-	int ch;
 
 	col = 0;
 	scrw = scr_wid;
diff --git a/commands/elle/eefill.c b/commands/elle/eefill.c
index f46a6506a..50d7d28d5 100644
--- a/commands/elle/eefill.c
+++ b/commands/elle/eefill.c
@@ -92,7 +92,7 @@ f_sfpref()
  */
 tstfillp(lim)
 int lim;
-{	register int i, c;
+{	register int i;
 	register char *cp;
 	chroff savdot;
 
@@ -260,7 +260,7 @@ int c;
 fill_cur_line()
 {
 	register int foundit, i;
-	chroff lastbrkdot, boldot, eoldot;
+	chroff lastbrkdot, boldot;
 
 	boldot = e_boldot();
 
diff --git a/commands/elle/eeterm.c b/commands/elle/eeterm.c
index 99429c255..a409f7777 100644
--- a/commands/elle/eeterm.c
+++ b/commands/elle/eeterm.c
@@ -988,8 +988,7 @@ static int tstrlen(), tstrlp();
 static int
 getcap(stype)
 char *stype;
-{	register char *t;
-	register int i;
+{       register int i;
 	int buflen;
 	char *tcbuf, *tcbptr;		/* Pointers into termcap buffer */
 	char tmpstr[4];
diff --git a/commands/elle/sberr.c b/commands/elle/sberr.c
index 168727f4e..4079a05ab 100644
--- a/commands/elle/sberr.c
+++ b/commands/elle/sberr.c
@@ -349,7 +349,6 @@ sbe_sdtab(pt, p, phys)
 register struct ptab *pt;
 int p, phys;
 {	register struct sdblk *sd;
-	register int res;
 
 	pt->pt_pflag = (p ? PTF_PRF : 0) | (phys ? PTF_SDPHYS : 0)
 			| PTF_OVFERR;
@@ -397,7 +396,7 @@ struct ptab *pt;
 	register struct smblk *sm;
 	struct sbfile *savfile;
 	chroff lastaddr;
-	int p, res, savidx, phys;
+	int p, savidx, phys;
 
 	phys = pt->pt_pflag&PTF_SDPHYS;	/* Set up physflag */
 	if(phys && (sd->sdfile == 0))	/* Ignore non-phys stuff if phys */
diff --git a/commands/simple/backup.c b/commands/simple/backup.c
index 4a72a1740..5d0127a5c 100644
--- a/commands/simple/backup.c
+++ b/commands/simple/backup.c
@@ -89,11 +89,11 @@ int main(argc, argv)
 int argc;
 char *argv[];
 {
-  int ct, n, m, fd;
+  int n, m;
   char *dir1, *dir2, *cp, c;
   struct stat s;
   struct dirent *e;
-  DIR *DIR1, *DIR2;
+  DIR *DIR1;
 
   (void) sync();
 
diff --git a/commands/simple/cleantmp.c b/commands/simple/cleantmp.c
index a0d403e73..3c4d5a9c6 100644
--- a/commands/simple/cleantmp.c
+++ b/commands/simple/cleantmp.c
@@ -181,7 +181,7 @@ unsigned ihash(const char *name)
 	return h & (arraysize(ignore_list) - 1);
 }
 
-void do_ignore(int add, char *name)
+void do_ignore(int add, const char *name)
 /* Add or remove a file to/from the list of files to ignore. */
 {
 	struct file **ipp, *ip;
@@ -208,7 +208,7 @@ void do_ignore(int add, char *name)
 	}
 }
 
-int is_ignored(char *name)
+int is_ignored(const char *name)
 /* Is a file in the list of ignored files? */
 {
 	struct file *ip;
diff --git a/commands/simple/cp.c b/commands/simple/cp.c
index d4e8745d1..71e191c19 100644
--- a/commands/simple/cp.c
+++ b/commands/simple/cp.c
@@ -346,7 +346,7 @@ static char *link_islink(const struct stat *stp, const char *file)
     return nil;
 }
 
-int trylink(const char *src, const char *dst, struct stat *srcst,
+int trylink(const char *src, const char *dst, const struct stat *srcst,
 			const struct stat *dstst)
 /* Keep the link structure intact if src has been seen before. */
 {
diff --git a/commands/simple/devsize.c b/commands/simple/devsize.c
index 250dda055..863c95452 100644
--- a/commands/simple/devsize.c
+++ b/commands/simple/devsize.c
@@ -23,8 +23,6 @@ unsigned long sizeup(char *);
 
 int main(int argc, char *argv[])
 {
-  int sec;
-
   if(argc != 2) {
 	fprintf(stderr, "Usage: %s <device>\n", argv[0]);
 	return 1;
@@ -41,7 +39,6 @@ char *device;
   int fd;
   struct partition entry;
   unsigned long d;
-  struct stat st;
 
   if ((fd = open(device, O_RDONLY)) == -1) {
   	perror("sizeup open");
diff --git a/commands/simple/dumpcore.c b/commands/simple/dumpcore.c
index 62e03170d..fe2078940 100644
--- a/commands/simple/dumpcore.c
+++ b/commands/simple/dumpcore.c
@@ -70,8 +70,6 @@ int adjust_stack(pid_t pid, struct mem_map *seg)
 
 int write_seg(int fd, pid_t pid, int seg, off_t seg_off, phys_bytes seg_bytes)
 {
-  int r;
-  off_t off;
   ssize_t w;
   static char buf[CLICK_SIZE];
   struct ptrace_range pr;
diff --git a/commands/simple/finger.c b/commands/simple/finger.c
index 900b325ac..a1ce1fdd3 100644
--- a/commands/simple/finger.c
+++ b/commands/simple/finger.c
@@ -152,7 +152,6 @@ main(argc, argv)
 	int argc;
 	register char **argv;
 {
-	FILE *fp;
 	register char *s;
 
 	prog_name= argv[0];
@@ -620,8 +619,6 @@ decode(pers)
 {
 	char buffer[256];
 	register char *bp, *gp, *lp;
-	int alldigits;
-	int hasspace;
 	int len;
 
 	pers->realname = 0;
@@ -888,9 +885,7 @@ netfinger(name)
 	char *name;
 {
 	char *host;
-	char fname[100];
 	struct hostent *hp;
-	struct servent *sp;
 	int s, result;
 #if !_MINIX
 	char *rindex();
diff --git a/commands/simple/getty.c b/commands/simple/getty.c
index d4feb4541..2275e2c4f 100644
--- a/commands/simple/getty.c
+++ b/commands/simple/getty.c
@@ -77,7 +77,7 @@ int readch(void)
 
 /* Handle the process of a GETTY.
  */
-void do_getty(char *name, size_t len, char **args, char *ttyname)
+void do_getty(char *name, size_t len, char **args, const char *ttyname)
 {
   register char *np, *s, *s0;
   int ch;
diff --git a/drivers/audio/common/audio_fw.c b/drivers/audio/common/audio_fw.c
index ba2ee458a..766ef3eff 100644
--- a/drivers/audio/common/audio_fw.c
+++ b/drivers/audio/common/audio_fw.c
@@ -198,7 +198,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info))
 {
 /* Initialize the audio driver framework. */
   return init_driver();
diff --git a/drivers/audio/es1371/AC97.c b/drivers/audio/es1371/AC97.c
index 276476d6f..5ca447073 100644
--- a/drivers/audio/es1371/AC97.c
+++ b/drivers/audio/es1371/AC97.c
@@ -7,7 +7,7 @@
 /* AC97 Mixer and Mode control function prototypes */
 
 FORWARD _PROTOTYPE( int  AC97_read, 
-		(DEV_STRUCT * pCC, u16_t wAddr, u16_t *data) );
+		(const DEV_STRUCT * pCC, u16_t wAddr, u16_t *data) );
 FORWARD _PROTOTYPE( int  AC97_write, 
 		(const DEV_STRUCT * pCC, u16_t wAddr, u16_t wData) );
 FORWARD _PROTOTYPE( void set_src_sync_state, (int state) );
@@ -133,7 +133,7 @@ u16_t  wBaseAddr = pCC->base;
 }
 
 
-PRIVATE int AC97_read (DEV_STRUCT * pCC, u16_t wAddr, u16_t *data)
+PRIVATE int AC97_read (const DEV_STRUCT * pCC, u16_t wAddr, u16_t *data)
 {
 u32_t dtemp, i;
 u16_t  base = pCC->base;
diff --git a/drivers/audio/es1371/sample_rate_converter.c b/drivers/audio/es1371/sample_rate_converter.c
index 1d74df510..916d67685 100644
--- a/drivers/audio/es1371/sample_rate_converter.c
+++ b/drivers/audio/es1371/sample_rate_converter.c
@@ -147,7 +147,7 @@ PRIVATE int src_reg_write(const DEV_STRUCT * DSP, u16_t reg, u16_t val) {
 }
 
 
-void src_set_rate(DEV_STRUCT * DSP, char base, u16_t rate) {
+void src_set_rate(const DEV_STRUCT * DSP, char base, u16_t rate) {
 	u32_t    freq, dtemp, i;
 	u16_t     N, truncM, truncStart, wtemp;
 
diff --git a/drivers/audio/es1371/sample_rate_converter.h b/drivers/audio/es1371/sample_rate_converter.h
index c093c25bf..9da3c8d29 100644
--- a/drivers/audio/es1371/sample_rate_converter.h
+++ b/drivers/audio/es1371/sample_rate_converter.h
@@ -6,7 +6,7 @@
 #include "pci_helper.h"
 
 _PROTOTYPE( int src_init, (DEV_STRUCT * DSP) );
-_PROTOTYPE( void src_set_rate, (DEV_STRUCT * DSP, char src_base, u16_t rate) );
+_PROTOTYPE( void src_set_rate, (const DEV_STRUCT * DSP, char src_base, u16_t rate) );
 
 #define SRC_SYNTH_BASE      0x70
 #define SRC_DAC_BASE        0x74
diff --git a/drivers/bios_wini/bios_wini.c b/drivers/bios_wini/bios_wini.c
index 2ac72d9be..2e1c36b49 100644
--- a/drivers/bios_wini/bios_wini.c
+++ b/drivers/bios_wini/bios_wini.c
@@ -514,7 +514,7 @@ struct partition *entry;
 /*============================================================================*
  *				w_other				      *
  *============================================================================*/
-PRIVATE int w_other(struct driver *dr, message *m)
+PRIVATE int w_other(struct driver *UNUSED(dr), message *m)
 {
         int r;
 
diff --git a/drivers/dec21140A/dec21140A.c b/drivers/dec21140A/dec21140A.c
index 183709131..797383495 100644
--- a/drivers/dec21140A/dec21140A.c
+++ b/drivers/dec21140A/dec21140A.c
@@ -30,7 +30,7 @@ _PROTOTYPE( PRIVATE void  io_outl,           (u16_t, u32_t);                 );
 _PROTOTYPE( PRIVATE void  do_conf,           (const message *);              );
 _PROTOTYPE( PRIVATE void  do_get_name,       (message *);                    );
 _PROTOTYPE( PRIVATE void  do_get_stat_s,     (message *);                    );
-_PROTOTYPE( PRIVATE void  do_interrupt,      (dpeth_t *);                    );
+_PROTOTYPE( PRIVATE void  do_interrupt,      (const dpeth_t *);              );
 _PROTOTYPE( PRIVATE void  do_reply,          (dpeth_t *, int, int);          );
 _PROTOTYPE( PRIVATE void  do_vread_s,        (const message *, int);         );
 _PROTOTYPE( PRIVATE void  do_watchdog,       (void *);                       );
@@ -42,7 +42,7 @@ _PROTOTYPE( PRIVATE void  de_first_init,     (dpeth_t *);                    );
 _PROTOTYPE( PRIVATE void  de_reset,          (const dpeth_t *);              );
 _PROTOTYPE( PRIVATE void  de_hw_conf,        (const dpeth_t *);              );
 _PROTOTYPE( PRIVATE void  de_start,          (const dpeth_t *);              );
-_PROTOTYPE( PRIVATE void  de_setup_frame,    (dpeth_t *);                    );
+_PROTOTYPE( PRIVATE void  de_setup_frame,    (const dpeth_t *);              );
 _PROTOTYPE( PRIVATE u16_t de_read_rom,       (const dpeth_t *, u8_t, u8_t);  );
 _PROTOTYPE( PRIVATE int   de_calc_iov_size,  (iovec_dat_s_t *);              );
 _PROTOTYPE( PRIVATE void  de_next_iov,       (iovec_dat_s_t *);              );
@@ -707,7 +707,7 @@ PRIVATE void de_first_init(dpeth_t *dep)
   sys_irqenable(&dep->de_hook);
 }
 
-PRIVATE void do_interrupt(dpeth_t *dep){  
+PRIVATE void do_interrupt(const dpeth_t *dep){  
   u32_t val;
   val = io_inl(CSR_ADDR(dep, CSR5));
 
@@ -763,7 +763,7 @@ PRIVATE void de_start(const dpeth_t *dep){
   io_outl(CSR_ADDR(dep, CSR6), val);
 }
 
-PRIVATE void de_setup_frame(dpeth_t *dep){
+PRIVATE void de_setup_frame(const dpeth_t *dep){
   int i;
   u32_t val;
 
diff --git a/drivers/dpeth/dp.c b/drivers/dpeth/dp.c
index 37511e2e8..31c008360 100644
--- a/drivers/dpeth/dp.c
+++ b/drivers/dpeth/dp.c
@@ -155,7 +155,7 @@ static void dp_confaddr(dpeth_t * dep)
 **  Function:	Gets the default settings from 'dp_conf' table and
 **  		modifies them from the environment.
 */
-static void update_conf(dpeth_t * dep, dp_conf_t * dcp)
+static void update_conf(dpeth_t * dep, const dp_conf_t * dcp)
 {
   static char dpc_fmt[] = "x:d:x";
   long val;
@@ -184,7 +184,7 @@ static void update_conf(dpeth_t * dep, dp_conf_t * dcp)
 **  Name:	void do_dump(message *mp)
 **  Function:	Displays statistics on screen (SFx key from console)
 */
-static void do_dump(message *mp)
+static void do_dump(const message *mp)
 {
   dpeth_t *dep;
   int port;
@@ -244,7 +244,7 @@ static void get_userdata_s(int user_proc, cp_grant_id_t grant,
 **  Name:	void do_first_init(dpeth_t *dep, dp_conf_t *dcp);
 **  Function:	Init action to setup task
 */
-static void do_first_init(dpeth_t *dep, dp_conf_t *dcp)
+static void do_first_init(dpeth_t *dep, const dp_conf_t *dcp)
 {
 
   if (dep->de_linmem != 0) {
@@ -275,7 +275,7 @@ static void do_first_init(dpeth_t *dep, dp_conf_t *dcp)
 **  Function:	Checks for hardware presence.
 **  		Provides initialization of hardware and data structures
 */
-static void do_init(message * mp)
+static void do_init(const message * mp)
 {
   int port;
   dpeth_t *dep;
@@ -395,7 +395,7 @@ static int calc_iovec_size(iovec_dat_s_t * iovp)
 **  Name:	void do_vwrite_s(message *mp)
 **  Function:
 */
-static void do_vwrite_s(message * mp)
+static void do_vwrite_s(const message * mp)
 {
   int port, size;
   dpeth_t *dep;
@@ -436,7 +436,7 @@ static void do_vwrite_s(message * mp)
 **  Name:	void do_vread_s(message *mp, int vectored)
 **  Function:
 */
-static void do_vread_s(message * mp)
+static void do_vread_s(const message * mp)
 {
   int port, size;
   dpeth_t *dep;
@@ -479,7 +479,7 @@ static void do_vread_s(message * mp)
 **  Name:	void do_getstat_s(message *mp)
 **  Function:	Reports device statistics.
 */
-static void do_getstat_s(message * mp)
+static void do_getstat_s(const message * mp)
 {
   int port, rc;
   dpeth_t *dep;
@@ -517,7 +517,7 @@ message *mp;
 **  Name:	void do_stop(message *mp)
 **  Function:	Stops network interface.
 */
-static void do_stop(message * mp)
+static void do_stop(const message * mp)
 {
   int port;
   dpeth_t *dep;
@@ -537,7 +537,7 @@ static void do_stop(message * mp)
   return;
 }
 
-static void do_watchdog(void *message)
+static void do_watchdog(const void *UNUSED(message))
 {
 
   DEBUG(printf("\t no reply"));
@@ -574,7 +574,6 @@ EXTERN char **env_argv;
 PUBLIC int main(int argc, char **argv)
 {
   message m;
-  dpeth_t *dep;
   int rc;
 
   /* SEF local startup. */
@@ -659,7 +658,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *UNUSED(info))
 {
 /* Initialize the dpeth driver. */
   int rc, fkeys, sfkeys, tasknr;
diff --git a/drivers/e1000/e1000.c b/drivers/e1000/e1000.c
index f53ea991c..d19dc0e0a 100644
--- a/drivers/e1000/e1000.c
+++ b/drivers/e1000/e1000.c
@@ -55,7 +55,7 @@ _PROTOTYPE( PRIVATE void e1000_reg_unset, (e1000_t *e, uint32_t reg,
 _PROTOTYPE( PRIVATE u16_t eeprom_eerd, (void *e, int reg)		);
 _PROTOTYPE( PRIVATE u16_t eeprom_ich,  (void *e, int reg)		);
 _PROTOTYPE( PRIVATE int eeprom_ich_init, (e1000_t *e)		        );
-_PROTOTYPE( PRIVATE int eeprom_ich_cycle, (e1000_t *e, u32_t timeout)   );
+_PROTOTYPE( PRIVATE int eeprom_ich_cycle, (const e1000_t *e, u32_t timeout) );
 _PROTOTYPE( PRIVATE void reply, (e1000_t *e, int err, int may_block)	);
 _PROTOTYPE( PRIVATE void mess_reply, (message *req, message *reply)	);
 
@@ -135,7 +135,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info))
 {
 /* Initialize the e1000 driver. */
     int r;
@@ -1083,7 +1083,7 @@ out:
 /*===========================================================================* 
  *                              eeprom_ich_cycle                             * 
  *===========================================================================*/
-PRIVATE int eeprom_ich_cycle(e1000_t *e, u32_t timeout)
+PRIVATE int eeprom_ich_cycle(const e1000_t *e, u32_t timeout)
 {
     union ich8_hws_flash_ctrl hsflctl;
     union ich8_hws_flash_status hsfsts;
diff --git a/drivers/filter/crc.c b/drivers/filter/crc.c
index 109407cc5..356018b7e 100644
--- a/drivers/filter/crc.c
+++ b/drivers/filter/crc.c
@@ -63,7 +63,7 @@ static unsigned long crctab[] = {
   0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
 };
 
-unsigned long compute_crc( unsigned char *b, size_t n)
+unsigned long compute_crc(const unsigned char *b, size_t n)
 {
   int i;
   unsigned long s = 0;       
diff --git a/drivers/filter/crc.h b/drivers/filter/crc.h
index ed38d9793..a9cfa4657 100644
--- a/drivers/filter/crc.h
+++ b/drivers/filter/crc.h
@@ -1,6 +1,6 @@
 #ifndef _CRC_H
 #define _CRC_H
 
-extern unsigned long compute_crc(unsigned char *b, size_t n);
+extern unsigned long compute_crc(const unsigned char *b, size_t n);
 
 #endif /* _CRC_H */
diff --git a/drivers/filter/driver.c b/drivers/filter/driver.c
index c554cd330..00db8d001 100644
--- a/drivers/filter/driver.c
+++ b/drivers/filter/driver.c
@@ -752,7 +752,7 @@ static int do_sendrec_both(message *m1, message *m2)
 /*===========================================================================*
  *				do_sendrec_one				     *
  *===========================================================================*/
-static int do_sendrec_one(message *m1, message *m2)
+static int do_sendrec_one(message *m1, const message *m2)
 {
 	/* Only talk to the main driver. If something goes wrong, it will
 	 * be fixed elsewhere.
@@ -796,7 +796,7 @@ static int paired_sendrec(message *m1, message *m2, int both)
  *				single_grant				     *
  *===========================================================================*/
 static int single_grant(endpoint_t endpt, vir_bytes buf, int access,
-	cp_grant_id_t *gid, iovec_s_t vector[NR_IOREQS], size_t *sizep)
+	cp_grant_id_t *gid, iovec_s_t vector[NR_IOREQS], const size_t *sizep)
 {
 	/* Create grants for a vectored request to a single driver.
 	 */
@@ -873,7 +873,7 @@ static int paired_grant(char *buf1, char *buf2, int request,
 /*===========================================================================*
  *				single_revoke				     *
  *===========================================================================*/
-PRIVATE void single_revoke(cp_grant_id_t gid, iovec_s_t vector[NR_IOREQS],
+PRIVATE void single_revoke(cp_grant_id_t gid, const iovec_s_t vector[NR_IOREQS],
 	size_t *sizep, int count)
 {
 	/* Revoke all grants associated with a request to a single driver.
@@ -894,7 +894,8 @@ PRIVATE void single_revoke(cp_grant_id_t gid, iovec_s_t vector[NR_IOREQS],
 /*===========================================================================*
  *				paired_revoke				     *
  *===========================================================================*/
-static void paired_revoke(cp_grant_id_t *gids, iovec_s_t vectors[2][NR_IOREQS],
+static void paired_revoke(const cp_grant_id_t *gids,
+        iovec_s_t vectors[2][NR_IOREQS],
 	size_t *sizes, int count, int both)
 {
 	/* Revoke grants to drivers for a single request.
diff --git a/drivers/filter/inc.h b/drivers/filter/inc.h
index 454df114b..5a936872c 100644
--- a/drivers/filter/inc.h
+++ b/drivers/filter/inc.h
@@ -97,7 +97,7 @@ extern int read_write(u64_t pos, char *bufa, char *bufb, size_t *sizep,
 
 /* util.c */
 extern char *flt_malloc(size_t size, char *sbuf, size_t ssize);
-extern void flt_free(char *buf, size_t size, char *sbuf);
+extern void flt_free(char *buf, size_t size, const char *sbuf);
 extern char *print64(u64_t p);
 extern clock_t flt_alarm(clock_t dt);
 extern void flt_sleep(int secs);
diff --git a/drivers/filter/sum.c b/drivers/filter/sum.c
index e5554fbeb..18d3b2efd 100644
--- a/drivers/filter/sum.c
+++ b/drivers/filter/sum.c
@@ -152,8 +152,8 @@ static void make_group_sum(char *bufp, char *sump, sector_t sector, int index,
 /*===========================================================================*
  *				check_group_sum				     *
  *===========================================================================*/
-static int check_group_sum(char *bufp, char *sump, sector_t sector, int index,
- int count)
+static int check_group_sum(char *bufp, const char *sump, sector_t sector,
+  int index, int count)
 {
 	/* Check checksums in a group. Parameters are the same as in
 	 * make_group_sum(). Return OK if all checksums check out, or RET_REDO
diff --git a/drivers/filter/util.c b/drivers/filter/util.c
index ba43eb8eb..0eda31908 100644
--- a/drivers/filter/util.c
+++ b/drivers/filter/util.c
@@ -29,7 +29,7 @@ char *flt_malloc(size_t size, char *sbuf, size_t ssize)
 /*===========================================================================*
  *				flt_free				     *
  *===========================================================================*/
-void flt_free(char *buf, size_t size, char *sbuf)
+void flt_free(char *buf, size_t size, const char *sbuf)
 {	
 	/* Free a buffer previously allocated with flt_malloc().
 	 */
diff --git a/drivers/floppy/floppy.c b/drivers/floppy/floppy.c
index 6457591b6..33114dd1d 100644
--- a/drivers/floppy/floppy.c
+++ b/drivers/floppy/floppy.c
@@ -257,7 +257,7 @@ FORWARD _PROTOTYPE( void start_motor, (void) 				);
 FORWARD _PROTOTYPE( int seek, (void) 					);
 FORWARD _PROTOTYPE( int fdc_transfer, (int opcode) 			);
 FORWARD _PROTOTYPE( int fdc_results, (void) 				);
-FORWARD _PROTOTYPE( int fdc_command, (u8_t *cmd, int len) 		);
+FORWARD _PROTOTYPE( int fdc_command, (const u8_t *cmd, int len) 	);
 FORWARD _PROTOTYPE( void fdc_out, (int val) 				);
 FORWARD _PROTOTYPE( int recalibrate, (void) 				);
 FORWARD _PROTOTYPE( void f_reset, (void) 				);
@@ -1041,7 +1041,7 @@ PRIVATE int fdc_results(void)
  *				fdc_command				     *
  *===========================================================================*/
 PRIVATE int fdc_command(
-  u8_t *cmd,		/* command bytes */
+  const u8_t *cmd,	/* command bytes */
   int len		/* command length */
 )
 {
diff --git a/drivers/fxp/fxp.c b/drivers/fxp/fxp.c
index f031261f6..af44d779e 100644
--- a/drivers/fxp/fxp.c
+++ b/drivers/fxp/fxp.c
@@ -232,7 +232,7 @@ _PROTOTYPE( static void fxp_confaddr, (fxp_t *fp)			);
 _PROTOTYPE( static void fxp_rec_mode, (fxp_t *fp)			);
 _PROTOTYPE( static void fxp_writev, (message *mp, int from_int,
 							int vectored)	);
-_PROTOTYPE( static void fxp_writev_s, (message *mp, int from_int)	);
+_PROTOTYPE( static void fxp_writev_s, (const message *mp, int from_int)	);
 _PROTOTYPE( static void fxp_readv, (message *mp, int from_int, 
 							int vectored)	);
 _PROTOTYPE( static void fxp_readv_s, (message *mp, int from_int)	);
@@ -367,7 +367,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info))
 {
 /* Initialize the fxp driver. */
 	int r;
@@ -1295,7 +1295,7 @@ suspend:
 /*===========================================================================*
  *				fxp_writev_s				     *
  *===========================================================================*/
-static void fxp_writev_s(message *mp, int from_int)
+static void fxp_writev_s(const message *mp, int from_int)
 {
 	cp_grant_id_t iov_grant;
 	vir_bytes iov_offset;
diff --git a/drivers/lance/lance.c b/drivers/lance/lance.c
index fe4976dd5..7415adc2f 100644
--- a/drivers/lance/lance.c
+++ b/drivers/lance/lance.c
@@ -105,7 +105,7 @@ _PROTOTYPE( static void ec_send, (ether_card_t *ec)                     );
 _PROTOTYPE( static void ec_recv, (ether_card_t *ec)                     );
 _PROTOTYPE( static void do_vwrite_s, 
             (message *mp, int from_int)                              );
-_PROTOTYPE( static void do_vread_s, (message *mp)                  );
+_PROTOTYPE( static void do_vread_s, (const message *mp)                  );
 _PROTOTYPE( static void ec_user2nic,
             (ether_card_t *dep, iovec_dat_t *iovp,
              vir_bytes offset, int nic_addr,
@@ -372,7 +372,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *UNUSED(info))
 {
 /* Initialize the lance driver. */
    int r;
@@ -1067,7 +1067,7 @@ ether_card_t *ec;
 /*===========================================================================*
  *                              do_vread_s                                   *
  *===========================================================================*/
-static void do_vread_s(message *mp)
+static void do_vread_s(const message *mp)
 {
    int port, count, r;
    ether_card_t *ec;
diff --git a/drivers/log/log.c b/drivers/log/log.c
index 1d553f219..79dddd303 100644
--- a/drivers/log/log.c
+++ b/drivers/log/log.c
@@ -99,7 +99,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *UNUSED(info))
 {
 /* Initialize the log driver. */
   int i;
diff --git a/drivers/orinoco/hermes.c b/drivers/orinoco/hermes.c
index 39996d76e..b9ff7141c 100644
--- a/drivers/orinoco/hermes.c
+++ b/drivers/orinoco/hermes.c
@@ -103,7 +103,7 @@ void hermes_struct_init (hermes_t * hw, u32_t address,
  * write HERMES_PCI_COR_MASK to the Configuration Option Register            *
  *****************************************************************************/
 int hermes_cor_reset (hermes_t *hw) {
-	int k, i;
+	int k;
 	u16_t reg;
 
 	/* Assert the reset until the card notice */
@@ -399,7 +399,6 @@ static int hermes_bap_seek (hermes_t * hw, int bap, u16_t id, u16_t offset) {
 	 * buffer */
 	int sreg = bap ? HERMES_SELECT1 : HERMES_SELECT0;
 	int oreg = bap ? HERMES_OFFSET1 : HERMES_OFFSET0;
-	int resp0;
 	int k;
 	u16_t reg;
 
@@ -743,7 +742,7 @@ void hermes_read_words (hermes_t * hw, int off, void *buf, unsigned count) {
  * registers are supported, but accessing I/O spaced registers should be     *
  * quite trivial                                                             *
  *****************************************************************************/
-u16_t hermes_read_reg (hermes_t * hw, u16_t off) {
+u16_t hermes_read_reg (const hermes_t * hw, u16_t off) {
 	int v = 0;
 	v = *((int *)(hw->locmem + (off << hw->reg_spacing)));
 	return (u16_t) v;
@@ -756,7 +755,7 @@ u16_t hermes_read_reg (hermes_t * hw, u16_t off) {
  * registers are supported, but accessing I/O spaced registers should be     *
  * quite trivial                                                             *
  *****************************************************************************/
-void hermes_write_reg (hermes_t * hw, u16_t off, u16_t val) {
+void hermes_write_reg (const hermes_t * hw, u16_t off, u16_t val) {
 	int v = (int) val;	
 	*(int *)(hw->locmem + (off << hw->reg_spacing)) = v;
 }
diff --git a/drivers/orinoco/hermes.h b/drivers/orinoco/hermes.h
index 38a79be9b..77109c116 100644
--- a/drivers/orinoco/hermes.h
+++ b/drivers/orinoco/hermes.h
@@ -301,8 +301,9 @@ struct hermes_idstring
 #define HERMES_RECLEN_TO_BYTES(n) ( ((n)-1) * 2 )
 
 /* Function prototypes */
-_PROTOTYPE (u16_t hermes_read_reg, (hermes_t * hw, u16_t off));
-_PROTOTYPE (void  hermes_write_reg, (hermes_t * hw, u16_t off, u16_t val));
+_PROTOTYPE (u16_t hermes_read_reg, (const hermes_t * hw, u16_t off));
+_PROTOTYPE (void  hermes_write_reg, (const hermes_t * hw, u16_t off,
+    u16_t val));
 _PROTOTYPE (void  hermes_struct_init, (hermes_t * hw, u32_t address,
 					int io_space, int reg_spacing));
 _PROTOTYPE (int  hermes_init, (hermes_t * hw));
diff --git a/drivers/orinoco/orinoco.c b/drivers/orinoco/orinoco.c
index c0394df41..e91f3c204 100644
--- a/drivers/orinoco/orinoco.c
+++ b/drivers/orinoco/orinoco.c
@@ -384,7 +384,6 @@ PRIVATE void sef_cb_signal_handler(int signo)
  * card                                                                      *
  *****************************************************************************/
 static void check_int_events(void) {
-	int i;
 	t_or *orp;
 
 	/* the interrupt message doesn't contain information about the port, try
@@ -427,10 +426,7 @@ static void or_getname(message *mp) {
  *****************************************************************************/
 static void do_hard_int(void)
 {
-	u16_t evstat;
-	hermes_t *hw;
 	int i,s;
-	t_or *orp;
 
 	for (i=0; i < OR_PORT_NR; i ++) {
 		/* Run interrupt handler at driver level. */
@@ -454,7 +450,6 @@ static void or_reset() {
 	static clock_t last_reset, now;	
 	t_or *orp;
 	int i, j, r;
-	u16_t irqmask;
 
 	if (OK != (r = getuptime(&now)))
 		panic("orinoco: getuptime() failed: %d", r);
@@ -499,8 +494,6 @@ static void or_reset() {
 static void or_dump (message *m)
  {
 	t_or *orp;
-	int err;
-	u16_t evstat =0, d;
 
 	for (orp = or_table; orp < or_table + OR_PORT_NR; orp++) {
 		if(orp->or_mode == OR_M_DISABLED) {
@@ -527,11 +520,10 @@ static void or_dump (message *m)
  * The main initialization function, called when a DL_INIT message comes in. *
  *****************************************************************************/
 static void or_init (message * mp) {
-	int port, err, i;
+	int port;
 	t_or *orp;
 	message reply;
 	static int first_time = 1;
-	clock_t t0,t1;
 
 	if (first_time) {
 		first_time = 0;
@@ -657,9 +649,10 @@ static void or_pci_conf () {
  * Try to find the card based on information provided by pci and get irq and *
  * bar                                                                       *
  *****************************************************************************/
-static int or_probe (t_or * orp) {
+static int or_probe (t_or * orp)
+{
 	u8_t ilr;
-	u32_t bar, reg, cpuspace_bar;
+	u32_t bar;
 	char *dname;
 	u16_t vid, did;
 	int i, r, devind, just_one;
@@ -748,9 +741,10 @@ static int or_probe (t_or * orp) {
  *                                                                           *
  * Map the memory mapped registers into user space memory                    *
  *****************************************************************************/
-static void map_hw_buffer(t_or *orp) {
+static void map_hw_buffer(t_or *orp)
+{
 	int r;
-	size_t o, size, reg_size;
+	size_t o, size;
 	char *buf, *abuf;	
 	hermes_t *hw = &(orp->hw);	
 
@@ -789,11 +783,10 @@ static void map_hw_buffer(t_or *orp) {
  * whether the card is memory mapped or in I/O space. Currently, only        *
  * memmory mapped is supported.                                              *
  *****************************************************************************/
-static u32_t or_get_bar (int devind, t_or * orp) {
-
-	u32_t bar, desired_bar;
-	int is_iospace, i;
-	u16_t check, check2;
+static u32_t or_get_bar (int devind, t_or * orp)
+{
+	u32_t bar;
+	int is_iospace;
 	hermes_t *hw = &(orp->hw);
 
 	/* bit 1 off the PCI_BAR register indicates whether the cards registers
@@ -850,7 +843,8 @@ static u32_t or_get_bar (int devind, t_or * orp) {
  *                                                                           *
  * Set the orinoco structure to default values                               *
  *****************************************************************************/
-static void or_init_struct (t_or * orp) {
+static void or_init_struct (t_or * orp)
+{
 	int i = 0;
 	static eth_stat_t empty_stat = { 0, 0, 0, 0, 0, 0 };
 
@@ -902,7 +896,8 @@ static void or_init_struct (t_or * orp) {
  * Initialize hardware and prepare for intercepting the interrupts. At the   *
  * end, the card is up and running                                           *
  *****************************************************************************/
-static void or_init_hw (t_or * orp) {
+static void or_init_hw (t_or * orp)
+{
 	int i, err, s;
 	hermes_t *hw = &(orp->hw);
 	static int first_time = TRUE;
@@ -971,13 +966,10 @@ static void or_init_hw (t_or * orp) {
  * In our case, we are mostly interested in the MAC address for now          *
  *****************************************************************************/
 
-static void or_readrids (hermes_t * hw, t_or * orp) {
-	int err, len, i;
-	struct hermes_idstring nickbuf;
-	u16_t reclen, d;
-
+static void or_readrids (hermes_t * hw, t_or * orp)
+{
 	/* Read the MAC address */
-	err = hermes_read_ltv (hw, USER_BAP, HERMES_RID_CNFOWNMACADDR,
+	int err = hermes_read_ltv (hw, USER_BAP, HERMES_RID_CNFOWNMACADDR,
 			       ETH_ALEN, NULL, &orp->or_address);
 	if (err) {
 		printf ("%s: failed to read MAC address!\n", orp->or_name);
@@ -992,10 +984,11 @@ static void or_readrids (hermes_t * hw, t_or * orp) {
  * Write some default rids to the card. A rid (resource identifier)          *
  * is a data item in the firmware, some configuration variable, e.g. WEP key *
  *****************************************************************************/
-static void or_writerids (hermes_t * hw, t_or * orp) {
+static void or_writerids (hermes_t * hw, t_or * orp)
+{
 	int err;
 	struct hermes_idstring idbuf;
-	u16_t port_type, max_data_len, reclen;
+	u16_t port_type;
 	static char essid[IW_ESSID_MAX_SIZE + 1];
 	static char wepkey0[LARGE_KEY_LENGTH + 1];
 
@@ -1111,12 +1104,9 @@ static void or_rec_mode (t_or * orp) {
  *****************************************************************************/
 static void or_handler (t_or *orp)
 {
-	int i, err, length, nr = 0;
+	int length;
 	u16_t evstat, events, fid;
-	hermes_t *hw;
-	struct hermes_tx_descriptor desc;
-	
-	hw = &(orp->hw);
+	hermes_t *hw = &(orp->hw);
 	
 beginning:
 	/* Retrieve which kind of event happened */
@@ -1296,7 +1286,8 @@ next:
  * Will be called regularly to see whether the driver has crashed. If that   *
  * condition is detected, reset the driver and card                          *
  *****************************************************************************/
-static void or_watchdog_f(timer_t *tp) {
+static void or_watchdog_f(timer_t *tp)
+{
 	int i;
 	t_or *orp;
 	
@@ -1334,7 +1325,8 @@ static void or_watchdog_f(timer_t *tp) {
  *                mess_reply                                                 *
  *****************************************************************************/
 
-static void mess_reply (message * req, message * reply_mess) {
+static void mess_reply (message * req, message * reply_mess)
+{
 	if (send (req->m_source, reply_mess) != 0)
 		panic("orinoco: unable to mess_reply");
 
@@ -1348,19 +1340,17 @@ static void mess_reply (message * req, message * reply_mess) {
  * of or_writev_s. We left out the comments. For an explanation, see         *
  * or_writev_s                                                               *
 ******************************************************************************/
-static void or_writev (message * mp, int from_int, int vectored) {
-	int port, or_client, count, size, err, data_len, data_off, tx_head;
-	int o, j, n, i, s, p, cps ;
+static void or_writev (message * mp, int from_int, int vectored)
+{
+	int port, or_client, count, size, err, data_len, data_off;
+	int o, j, n, i, s, p, cps;
 	struct ethhdr *eh;
 	t_or *orp;
-	clock_t timebefore, t0;	
-	phys_bytes phys_user;
 	hermes_t *hw;
 	struct hermes_tx_descriptor desc;
 	struct header_struct hdr;
 
 	iovec_t *iovp;
-	phys_bytes phys_databuf;
 	u16_t txfid;
 	static u8_t databuf[IEEE802_11_DATA_LEN + ETH_HLEN + 2 + 1];
 	memset (databuf, 0, IEEE802_11_DATA_LEN + ETH_HLEN + 3);
@@ -1757,9 +1747,10 @@ static void reply (t_or * orp, int err, int may_block) {
  *                                                                           *
  * Process information which comes in from the card                          *
  *****************************************************************************/
-static void or_ev_info (t_or * orp) {
+static void or_ev_info (t_or * orp)
+{
 	u16_t infofid;
-	int err, len, type, i;
+	int err, len, type;
 	hermes_t *hw = &orp->hw;
 
 	struct {
@@ -1903,10 +1894,8 @@ static void print_linkstatus (t_or * orp, u16_t status) {
  *                                                                           *
  * Process events which have been postponed in the interrupt handler         *
  *****************************************************************************/
-static void or_check_ints (t_or * orp) {
-	int or_flags;
-	hermes_t *hw = &orp->hw;
-
+static void or_check_ints (t_or * orp)
+{
 	if (orp->or_need_reset)
 		or_reset();
 	if ((orp->rx_first!=orp->rx_last) && (orp->or_flags & OR_F_READING)) {
@@ -1965,18 +1954,10 @@ static int is_ethersnap(struct header_struct *hdr)  {
  * or_readv_s                                                                *
  *****************************************************************************/
 static void or_readv (message * mp, int from_int, int vectored) {
-	int i, j, n, o, s, s1, dl_port, or_client, count, size, err, yep, cps;
-	port_t port;
-	clock_t timebefore;
-	unsigned amount, totlen, packlen;
-	struct hermes_rx_descriptor desc;
-	phys_bytes dst_phys;
-	u16_t d_start, d_end, status;
-	struct header_struct hdr;
-	int length, offset;
-	u32_t l, rxstat;
-	struct ethhdr *eh;
-	struct header_struct *h;
+	int i, j, n, o, s, dl_port;
+	int or_client, count;
+	int size, cps;
+	int length;
 	t_or *orp;
 	iovec_t *iovp;
 	u8_t *databuf;
@@ -2082,24 +2063,12 @@ suspend_readv :
  * Copy the data which is stored in orp->rx_buf[orp->rx_first] in the vector *
  * which was given with the message *mp                                      *
  *****************************************************************************/
-static void or_readv_s (message * mp, int from_int) {
-	int i, j, n, o, s, s1, dl_port, or_client, count, size, err, cps;
-	int iov_offset = 0, length, offset;
-	port_t port;
-	clock_t timebefore;
-	unsigned amount, totlen, packlen;
-	struct hermes_rx_descriptor desc;
-	phys_bytes dst_phys;
-	u16_t d_start, d_end, status;
-	struct header_struct hdr;
-	u32_t l, rxstat;
-	struct ethhdr *eh;
-	struct header_struct *h;
+static void or_readv_s (message * mp, int from_int)
+{
+	int i, j, n, o, s, dl_port, or_client, count, size, cps;
+	int iov_offset = 0, length;
 	t_or *orp;
-
 	iovec_s_t *iovp;
-	phys_bytes databuf_phys;
-
 	u8_t *databuf;
 
 	dl_port = mp->DL_PORT;
@@ -2315,7 +2284,8 @@ static int or_get_recvd_packet(t_or *orp, u16_t rxfid, u8_t *databuf) {
  * Return the statistics structure. The statistics aren't updated until now, *
  * so this won't return much interesting yet.                                *
  *****************************************************************************/
-static void or_getstat (message * mp) {
+static void or_getstat (message * mp)
+{
 	int r, port;
 	eth_stat_t stats;
 	t_or *orp;
diff --git a/drivers/readclock/readclock.c b/drivers/readclock/readclock.c
index c5c30a073..fdc37a622 100644
--- a/drivers/readclock/readclock.c
+++ b/drivers/readclock/readclock.c
@@ -94,7 +94,6 @@ int main(int argc, char **argv)
   time_t now, rtc;
   int i, s;
   unsigned char mach_id, cmos_state;
-  struct sysgetenv sysgetenv;
 
   /* SEF local startup. */
   env_setargs(argc, argv);
@@ -231,7 +230,6 @@ void errmsg(char *s)
 void get_time(struct tm *t)
 {
   int osec, n;
-  unsigned long i;
 
   do {
 	osec = -1;
diff --git a/drivers/rtl8139/rtl8139.c b/drivers/rtl8139/rtl8139.c
index 23c05c0f9..154d552ae 100644
--- a/drivers/rtl8139/rtl8139.c
+++ b/drivers/rtl8139/rtl8139.c
@@ -153,12 +153,12 @@ _PROTOTYPE( static void rl_init_hw, (re_t *rep)				);
 _PROTOTYPE( static void rl_reset_hw, (re_t *rep)			);
 _PROTOTYPE( static void rl_confaddr, (re_t *rep)			);
 _PROTOTYPE( static void rl_rec_mode, (re_t *rep)			);
-_PROTOTYPE( static void rl_readv, (message *mp, int from_int, 
+_PROTOTYPE( static void rl_readv, (const message *mp, int from_int, 
 							int vectored)	);
-_PROTOTYPE( static void rl_readv_s, (message *mp, int from_int)	);
-_PROTOTYPE( static void rl_writev, (message *mp, int from_int,
+_PROTOTYPE( static void rl_readv_s, (const message *mp, int from_int)	);
+_PROTOTYPE( static void rl_writev, (const message *mp, int from_int,
 							int vectored)	);
-_PROTOTYPE( static void rl_writev_s, (message *mp, int from_int)	);
+_PROTOTYPE( static void rl_writev_s, (const message *mp, int from_int)	);
 _PROTOTYPE( static void rl_check_ints, (re_t *rep)			);
 _PROTOTYPE( static void rl_report_link, (re_t *rep)			);
 _PROTOTYPE( static void mii_print_techab, (U16_t techab)		);
@@ -298,7 +298,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *UNUSED(info))
 {
 /* Initialize the rtl8139 driver. */
 #if RTL8139_FKEY
@@ -696,7 +696,7 @@ re_t *rep;
 	size_t rx_bufsize, tx_bufsize, tot_bufsize;
 	phys_bytes buf;
 	char *mallocbuf;
-	int fd, s, i, off;
+	int i, off;
 
 	/* Allocate receive and transmit buffers */
 	tx_bufsize= ETH_MAX_PACK_SIZE_TAGGED;
@@ -971,12 +971,11 @@ re_t *rep;
 /*===========================================================================*
  *				rl_readv				     *
  *===========================================================================*/
-static void rl_readv(message *mp, int from_int, int vectored)
+static void rl_readv(const message *mp, int from_int, int vectored)
 {
 	int i, j, n, o, s, s1, dl_port, re_client, count, size;
 	port_t port;
 	unsigned amount, totlen, packlen;
-	phys_bytes dst_phys;
 	u16_t d_start, d_end;
 	u32_t l, rxstat = 0x12345678;
 	re_t *rep;
@@ -1218,7 +1217,7 @@ suspend:
 /*===========================================================================*
  *				rl_readv_s				     *
  *===========================================================================*/
-static void rl_readv_s(message *mp, int from_int)
+static void rl_readv_s(const message *mp, int from_int)
 {
 	int i, j, n, o, s, s1, dl_port, re_client, count, size;
 	port_t port;
@@ -1444,7 +1443,7 @@ suspend:
 /*===========================================================================*
  *				rl_writev				     *
  *===========================================================================*/
-static void rl_writev(message *mp, int from_int, int vectored)
+static void rl_writev(const message *mp, int from_int, int vectored)
 {
 	phys_bytes phys_user;
 	int i, j, n, s, port, count, size;
@@ -1585,7 +1584,7 @@ suspend:
 /*===========================================================================*
  *				rl_writev_s				     *
  *===========================================================================*/
-static void rl_writev_s(message *mp, int from_int)
+static void rl_writev_s(const message *mp, int from_int)
 {
 	int i, j, n, s, port, count, size;
 	int tx_head, re_client;
@@ -2110,7 +2109,6 @@ re_t *rep;
 {
 	port_t port;
 	u8_t cr;
-	int i;
 	clock_t t0,t1;
 
 	rep->re_clear_rx= FALSE;
diff --git a/drivers/rtl8169/rtl8169.c b/drivers/rtl8169/rtl8169.c
index 0db59fed5..786b0f0a5 100644
--- a/drivers/rtl8169/rtl8169.c
+++ b/drivers/rtl8169/rtl8169.c
@@ -249,8 +249,8 @@ _PROTOTYPE( static void rl_init_hw, (re_t *rep)				);
 _PROTOTYPE( static void rl_reset_hw, (re_t *rep)			);
 _PROTOTYPE( static void rl_confaddr, (re_t *rep)			);
 _PROTOTYPE( static void rl_rec_mode, (re_t *rep)			);
-_PROTOTYPE( static void rl_readv_s, (message *mp, int from_int)	);
-_PROTOTYPE( static void rl_writev_s, (message *mp, int from_int)	);
+_PROTOTYPE( static void rl_readv_s, (const message *mp, int from_int)	);
+_PROTOTYPE( static void rl_writev_s, (const message *mp, int from_int)	);
 _PROTOTYPE( static void rl_check_ints, (re_t *rep)			);
 _PROTOTYPE( static void rl_report_link, (re_t *rep)			);
 _PROTOTYPE( static void rl_do_reset, (re_t *rep)			);
@@ -262,7 +262,7 @@ _PROTOTYPE( static void mess_reply, (message *req, message *reply)	);
 _PROTOTYPE( static void check_int_events, (void)			);
 _PROTOTYPE( static void do_hard_int, (void)				);
 _PROTOTYPE( static void rtl8169_dump, (void)				);
-_PROTOTYPE( static void dump_phy, (re_t *rep)				);
+_PROTOTYPE( static void dump_phy, (const re_t *rep)			);
 _PROTOTYPE( static void rl_handler, (re_t *rep)				);
 _PROTOTYPE( static void rl_watchdog_f, (timer_t *tp)			);
 
@@ -363,7 +363,7 @@ PRIVATE void sef_local_startup()
 /*===========================================================================*
  *		            sef_cb_init_fresh                                *
  *===========================================================================*/
-PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
+PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *UNUSED(info))
 {
 /* Initialize the rtl8169 driver. */
 	u32_t inet_proc_nr;
@@ -1283,7 +1283,7 @@ void transmittest(re_t *rep)
 /*===========================================================================*
  *				rl_readv_s				     *
  *===========================================================================*/
-static void rl_readv_s(message *mp, int from_int)
+static void rl_readv_s(const message *mp, int from_int)
 {
 	int i, j, n, s, dl_port, re_client, count, size, index;
 	port_t port;
@@ -1425,7 +1425,7 @@ suspend:
 /*===========================================================================*
  *				rl_writev_s				     *
  *===========================================================================*/
-static void rl_writev_s(message *mp, int from_int)
+static void rl_writev_s(const message *mp, int from_int)
 {
 	int i, j, n, s, port, count, size;
 	int tx_head, re_client;
@@ -1790,7 +1790,7 @@ message *reply_mess;
 		panic("unable to mess_reply");
 }
 
-static void dump_phy(re_t *rep)
+static void dump_phy(const re_t *rep)
 {
 #if VERBOSE
 	port_t port;
diff --git a/drivers/ti1225/ti1225.c b/drivers/ti1225/ti1225.c
index 5783497c8..8c94a925d 100644
--- a/drivers/ti1225/ti1225.c
+++ b/drivers/ti1225/ti1225.c
@@ -183,7 +183,7 @@ PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
 PRIVATE void hw_init(pp)
 struct port *pp;
 {
-	int i, r, devind, irq, socket;
+	int r, devind, irq;
 	u8_t v8;
 	u16_t v16;
 	u32_t v32;
@@ -311,7 +311,7 @@ PRIVATE void map_regs(struct port *pp, u32_t base)
 PRIVATE void do_int(pp)
 struct port *pp;
 {
-	int i, r, devind, vcc_5v, vcc_3v, vcc_Xv, vcc_Yv,
+	int r, devind, vcc_5v, vcc_3v, vcc_Xv, vcc_Yv,
 		socket_5v, socket_3v, socket_Xv, socket_Yv;
 	clock_t t0, t1;
 	u32_t csr_event, csr_present, csr_control;
diff --git a/drivers/tty/console.c b/drivers/tty/console.c
index 00d30adab..985f5608a 100644
--- a/drivers/tty/console.c
+++ b/drivers/tty/console.c
@@ -821,7 +821,6 @@ PUBLIC void do_video(message *m)
 		  case TIOCUNMAPMEM: {
 			int r, do_map;
 			struct mapreqvm mapreqvm;
-			void *result;
 
 			do_map= (m->REQUEST == TIOCMAPMEM);	/* else unmap */
 
diff --git a/drivers/tty/keyboard.c b/drivers/tty/keyboard.c
index 56295cdf7..9b9e77f90 100644
--- a/drivers/tty/keyboard.c
+++ b/drivers/tty/keyboard.c
@@ -1182,7 +1182,6 @@ int scode;			/* scan code for a function key */
  * in kb_init, where NONE is set to indicate there is no interest in the key.
  * Returns FALSE on a key release or if the key is not observable.
  */
-  message m;
   int key;
   int proc_nr;
 
diff --git a/drivers/tty/tty.c b/drivers/tty/tty.c
index af47414a6..324b56c82 100644
--- a/drivers/tty/tty.c
+++ b/drivers/tty/tty.c
@@ -161,8 +161,6 @@ PUBLIC int main(void)
   sef_local_startup();
 
   while (TRUE) {
-	int adflag = 0;
-
 	/* Check for and handle any events on any of the ttys. */
 	for (tp = FIRST_TTY; tp < END_TTY; tp++) {
 		if (tp->tty_events) handle_events(tp);
diff --git a/kernel/arch/i386/apic.c b/kernel/arch/i386/apic.c
index bc9233f01..9d39aa969 100644
--- a/kernel/arch/i386/apic.c
+++ b/kernel/arch/i386/apic.c
@@ -78,7 +78,7 @@ PRIVATE u32_t pci_config_intr_data;
 PRIVATE u32_t ioapic_extint_assigned = 0;
 PRIVATE int lapic_extint_assigned = 0;
 
-PRIVATE int calib_clk_handler(irq_hook_t * hook)
+PRIVATE int calib_clk_handler(irq_hook_t * UNUSED(hook))
 {
 	u32_t tcrt;
 	u64_t tsc;
diff --git a/kernel/arch/i386/memory.c b/kernel/arch/i386/memory.c
index c68b6bebb..8f6c4be7d 100644
--- a/kernel/arch/i386/memory.c
+++ b/kernel/arch/i386/memory.c
@@ -137,8 +137,8 @@ PRIVATE phys_bytes createpde(
 /*===========================================================================*
  *				lin_lin_copy				     *
  *===========================================================================*/
-PRIVATE int lin_lin_copy(struct proc *srcproc, vir_bytes srclinaddr, 
-	struct proc *dstproc, vir_bytes dstlinaddr, vir_bytes bytes)
+PRIVATE int lin_lin_copy(const struct proc *srcproc, vir_bytes srclinaddr, 
+	const struct proc *dstproc, vir_bytes dstlinaddr, vir_bytes bytes)
 {
 	u32_t addr;
 	proc_nr_t procslot;
@@ -476,7 +476,7 @@ PUBLIC int vm_lookup(const struct proc *proc, const vir_bytes virtual,
 /*===========================================================================*
  *                              vm_contiguous                                *
  *===========================================================================*/
-PUBLIC int vm_contiguous(struct proc *targetproc, u32_t vir_buf, size_t bytes)
+PUBLIC int vm_contiguous(const struct proc *targetproc, u32_t vir_buf, size_t bytes)
 {
 	int first = 1, r;
 	u32_t prev_phys = 0;    /* Keep lints happy. */
@@ -900,7 +900,7 @@ PUBLIC void arch_pre_exec(struct proc *pr, const u32_t ip, const u32_t sp)
 /*===========================================================================*
  *				arch_umap				     *
  *===========================================================================*/
-PUBLIC int arch_umap(struct proc *pr, vir_bytes offset, vir_bytes count,
+PUBLIC int arch_umap(const struct proc *pr, vir_bytes offset, vir_bytes count,
 	int seg, phys_bytes *addr)
 {
 	switch(seg) {
diff --git a/kernel/proto.h b/kernel/proto.h
index 58fed5f6e..8be84262e 100644
--- a/kernel/proto.h
+++ b/kernel/proto.h
@@ -162,10 +162,10 @@ _PROTOTYPE( void do_ser_debug, (void)					);
 _PROTOTYPE( int arch_get_params, (char *parm, int max));
 _PROTOTYPE( int arch_set_params, (char *parm, int max));
 _PROTOTYPE( void arch_pre_exec, (struct proc *pr, u32_t, u32_t));
-_PROTOTYPE( int arch_umap, (struct proc *pr, vir_bytes, vir_bytes,
+_PROTOTYPE( int arch_umap, (const struct proc *pr, vir_bytes, vir_bytes,
 	int, phys_bytes *));
 _PROTOTYPE( int arch_do_vmctl, (message *m_ptr, struct proc *p)); 
-_PROTOTYPE( int vm_contiguous, (struct proc *targetproc, vir_bytes vir_buf, size_t count));
+_PROTOTYPE( int vm_contiguous, (const struct proc *targetproc, vir_bytes vir_buf, size_t count));
 _PROTOTYPE( void proc_stacktrace, (struct proc *proc)	         );
 _PROTOTYPE( int vm_lookup, (const struct proc *proc, vir_bytes virtual, vir_bytes *result, u32_t *ptent));
 _PROTOTYPE( int delivermsg, (struct proc *target));
diff --git a/lib/libc/ip/getifaddrs.c b/lib/libc/ip/getifaddrs.c
index 748ae97eb..1872ae30b 100644
--- a/lib/libc/ip/getifaddrs.c
+++ b/lib/libc/ip/getifaddrs.c
@@ -18,7 +18,7 @@ getifaddrs(struct ifaddrs **ifap)
 {
 	static int fd = -1;
 	nwio_ipconf_t ipconf;
-	int flags, err, r;
+	int flags;
 	static struct ifaddrs ifa;
 	static struct sockaddr_in addr, netmask;
 
diff --git a/lib/libc/ip/recvfrom.c b/lib/libc/ip/recvfrom.c
index ce9656585..659535666 100644
--- a/lib/libc/ip/recvfrom.c
+++ b/lib/libc/ip/recvfrom.c
@@ -105,7 +105,6 @@ static ssize_t _udp_recvfrom(int socket, void *_RESTRICT buffer, size_t length,
 	int r, t_errno;
 	size_t buflen, len;
 	void *buf;
-	struct sockaddr_in *sinp;
 	udp_io_hdr_t *io_hdrp;
 	struct sockaddr_in sin;
 
diff --git a/lib/libc/ip/setsockopt.c b/lib/libc/ip/setsockopt.c
index 58922b9f6..c5d362ac5 100644
--- a/lib/libc/ip/setsockopt.c
+++ b/lib/libc/ip/setsockopt.c
@@ -169,8 +169,6 @@ static int _tcp_setsockopt(int socket, int level, int option_name,
 static int _udp_setsockopt(int socket, int level, int option_name,
 	const void *option_value, socklen_t option_len)
 {
-	int i;
-
 #if DEBUG
 	fprintf(stderr, "_udp_setsocketopt: level %d, name %d\n",
 		level, option_name);
diff --git a/lib/libc/other/_mount.c b/lib/libc/other/_mount.c
index 5d930ae91..597b71256 100644
--- a/lib/libc/other/_mount.c
+++ b/lib/libc/other/_mount.c
@@ -18,7 +18,6 @@
 PRIVATE int rs_down(char *label)
 {
 	char cmd[200];
-	message m;
 	if(strlen(_PATH_SERVICE)+strlen(label)+50 >= sizeof(cmd))
 		return -1;
 	sprintf(cmd, _PATH_SERVICE " down '%s'", label);
diff --git a/lib/libc/other/_seekdir.c b/lib/libc/other/_seekdir.c
index a341f9dc7..7c4159c30 100644
--- a/lib/libc/other/_seekdir.c
+++ b/lib/libc/other/_seekdir.c
@@ -1,7 +1,6 @@
 /*	seekdir()					Author: Kees J. Bot
  *								24 Apr 1989
  */
-#define nil 0
 #include <lib.h>
 #define lseek	_lseek
 #define readdir	_readdir
@@ -14,9 +13,7 @@
 int seekdir(DIR *dp, off_t pos)
 /* Seek to position pos in a directory. */
 {
-	int off;
-
-	if (dp == nil) { errno= EBADF; return -1; }
+	if (dp == NULL) { errno= EBADF; return -1; }
 
 	dp->_count= 0;
 
diff --git a/lib/libc/other/asynchio.c b/lib/libc/other/asynchio.c
index df6eb6ea5..ee7434bda 100644
--- a/lib/libc/other/asynchio.c
+++ b/lib/libc/other/asynchio.c
@@ -5,7 +5,6 @@
  * Thise are just stub routines that are call compatible with
  * the asynchio(3) library of Minix-vmd.  See asynchio.h.
  */
-#define nil 0
 #define alarm	_alarm
 #define ioctl	_ioctl
 #define read	_read
@@ -98,8 +97,8 @@ int asyn_wait(asynchio_t *asyn, int flags, struct timeval *to)
 		return 0;
 	}
 
-	if (to != nil) {
-		now= time(nil);
+	if (to != NULL) {
+		now= time(NULL);
 		if (to->tv_sec <= now) { errno= EINTR; return -1; }
 		old_timer= alarm(0);
 		new_sa.sa_handler= time_out;
@@ -129,7 +128,7 @@ int asyn_wait(asynchio_t *asyn, int flags, struct timeval *to)
 		asyn->errno= errno;
 		break;
 	}
-	if (to != nil) {
+	if (to != NULL) {
 		alarm(0);
 		sigaction(SIGALRM, &old_sa, (struct sigaction *)0);
 		alarm(old_timer);
diff --git a/lib/libc/other/fts.c b/lib/libc/other/fts.c
index 7a4023c5e..f9dc37b15 100644
--- a/lib/libc/other/fts.c
+++ b/lib/libc/other/fts.c
@@ -1209,7 +1209,6 @@ static int
 fts_ufslinks(FTS *sp, const FTSENT *ent)
 {
 	struct _fts_private *priv;
-	const char **cpp;
 
 	priv = (struct _fts_private *)sp;
 	priv->ftsp_linksreliable = 0;
diff --git a/lib/libc/other/initgroups.c b/lib/libc/other/initgroups.c
index d27554945..3f455793f 100644
--- a/lib/libc/other/initgroups.c
+++ b/lib/libc/other/initgroups.c
@@ -11,7 +11,7 @@ initgroups.c
 int initgroups(const char *name, gid_t basegid)
 {
   struct group *gr;
-  int r, found = 0, n = 0;
+  int r, n = 0;
   gid_t groups[NGROUPS];
 
   if((r = setgid(basegid)) < 0)
diff --git a/lib/libc/other/vectorio.c b/lib/libc/other/vectorio.c
index 20d007464..1e59e6959 100644
--- a/lib/libc/other/vectorio.c
+++ b/lib/libc/other/vectorio.c
@@ -75,7 +75,6 @@ static ssize_t vectorio(int fildes, const struct iovec *iov,
 	int iovcnt, int readwrite)
 {
 	int i;
-	struct stat statbuf;
 	ssize_t totallen;
 
 	/* parameter sanity checks */
diff --git a/lib/libc/posix/_mmap.c b/lib/libc/posix/_mmap.c
index a1bfd6638..a01602015 100644
--- a/lib/libc/posix/_mmap.c
+++ b/lib/libc/posix/_mmap.c
@@ -85,7 +85,6 @@ PUBLIC int vm_unmap(int endpt, void *addr)
 PUBLIC unsigned long vm_getphys(int endpt, void *addr)
 {
 	message m;
-	unsigned long ret;
 	int r;
 
 	m.VMPHYS_ENDPT = endpt;
@@ -100,7 +99,6 @@ PUBLIC unsigned long vm_getphys(int endpt, void *addr)
 PUBLIC u8_t vm_getrefcount(int endpt, void *addr)
 {
 	message m;
-	u8_t ret;
 	int r;
 
 	m.VMREFCNT_ENDPT = endpt;
diff --git a/lib/libc/posix/_ucontext.c b/lib/libc/posix/_ucontext.c
index 110133566..d7930e6ad 100644
--- a/lib/libc/posix/_ucontext.c
+++ b/lib/libc/posix/_ucontext.c
@@ -70,7 +70,7 @@ PUBLIC int getuctx(ucontext_t *ucp)
 PUBLIC void makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
 {
   va_list ap;
-  unsigned int *stack_top, *stack_guard;
+  unsigned int *stack_top;
 
   /* There are a number of situations that are erroneous, but we can't actually
      tell the caller something is wrong, because this is a void function.
@@ -158,7 +158,6 @@ PUBLIC void makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
 PUBLIC int swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
 {
   int r;
-  unsigned int *stack_guard;
 
   if ((oucp == NULL) || (ucp == NULL)) {
 	errno = EFAULT;
diff --git a/lib/libc/posix/getloadavg.c b/lib/libc/posix/getloadavg.c
index adca7d847..70253473b 100644
--- a/lib/libc/posix/getloadavg.c
+++ b/lib/libc/posix/getloadavg.c
@@ -41,7 +41,7 @@ int getloadavg(double *loadavg, int nelem)
   unfilled_ticks = TICKSPERSLOT - (loadinfo.last_clock % TICKSPERSLOT);
 
   for(p = 0; p < nelem; p++) {
-    int h, offset, slots;
+    int h, slots;
     double l = 0.0;
     int latest = loadinfo.proc_last_slot;
     slots = minutes[p] * 60 / _LOAD_UNIT_SECS;
diff --git a/lib/libdriver/driver.c b/lib/libdriver/driver.c
index 7a8a5c693..483c3cadc 100644
--- a/lib/libdriver/driver.c
+++ b/lib/libdriver/driver.c
@@ -126,7 +126,6 @@ int type;		/* Driver type (DRIVER_STD or DRIVER_ASYN) */
 
   int r, proc_nr;
   message mess;
-  sigset_t set;
 
   /* Init MQ library. */
   mq_init();
diff --git a/lib/libtimers/tmrs_clr.c b/lib/libtimers/tmrs_clr.c
index b8d2a732a..5b97570b3 100644
--- a/lib/libtimers/tmrs_clr.c
+++ b/lib/libtimers/tmrs_clr.c
@@ -11,7 +11,6 @@ clock_t *next_time;
 /* Deactivate a timer and remove it from the timers queue. 
  */
   timer_t **atp;
-  struct proc *p;
   clock_t prev_time;
 
   if(*tmrs)
diff --git a/lib/libutil/openpty.c b/lib/libutil/openpty.c
index ec6db2525..e28080076 100644
--- a/lib/libutil/openpty.c
+++ b/lib/libutil/openpty.c
@@ -29,9 +29,8 @@
 int openpty(int *amaster, int *aslave, char *name,
 	struct termios *termp, struct winsize *winp)
 {
-  char buff[128], temp[128];
+  char buff[128];
   register int i, j;
-  int pty_fd = -1, gr;
   static char tty_name[128];
   struct group *ttygroup;
   gid_t tty_gid = 0;
diff --git a/servers/ds/proto.h b/servers/ds/proto.h
index 1bd516595..c8ec34561 100644
--- a/servers/ds/proto.h
+++ b/servers/ds/proto.h
@@ -9,12 +9,12 @@ _PROTOTYPE(int main, (int argc, char **argv));
 /* store.c */
 _PROTOTYPE(int do_publish, (message *m_ptr));
 _PROTOTYPE(int do_retrieve, (message *m_ptr));
-_PROTOTYPE(int do_retrieve_label, (message *m_ptr));
+_PROTOTYPE(int do_retrieve_label, (const message *m_ptr));
 _PROTOTYPE(int do_subscribe, (message *m_ptr));
 _PROTOTYPE(int do_check, (message *m_ptr));
 _PROTOTYPE(int do_delete, (message *m_ptr));
 _PROTOTYPE(int do_snapshot, (message *m_ptr));
-_PROTOTYPE(int do_getsysinfo, (message *m_ptr));
+_PROTOTYPE(int do_getsysinfo, (const message *m_ptr));
 _PROTOTYPE(int sef_cb_init_fresh, (int type, sef_init_info_t *info));
 
 #endif
diff --git a/servers/ds/store.c b/servers/ds/store.c
index 53e83ad2e..e37088f7b 100644
--- a/servers/ds/store.c
+++ b/servers/ds/store.c
@@ -126,7 +126,7 @@ PRIVATE endpoint_t ds_getprocep(const char *s)
 /*===========================================================================*
  *				 check_auth				     *
  *===========================================================================*/
-PRIVATE int check_auth(struct data_store *p, endpoint_t ep, int perm)
+PRIVATE int check_auth(const struct data_store *p, endpoint_t ep, int perm)
 {
 /* Check authorization for a given type of permission. */
 	char *source;
@@ -141,7 +141,7 @@ PRIVATE int check_auth(struct data_store *p, endpoint_t ep, int perm)
 /*===========================================================================*
  *				get_key_name				     *
  *===========================================================================*/
-PRIVATE int get_key_name(message *m_ptr, char *key_name)
+PRIVATE int get_key_name(const message *m_ptr, char *key_name)
 {
 /* Get key name given an input message. */
   int r;
@@ -169,7 +169,7 @@ PRIVATE int get_key_name(message *m_ptr, char *key_name)
 /*===========================================================================*
  *			     check_snapshot_index			     *
  *===========================================================================*/
-PRIVATE int check_snapshot_index(struct data_store *dsp, int index)
+PRIVATE int check_snapshot_index(const struct data_store *dsp, int index)
 {
 /* See if the given snapshot index is valid. */
   int min;
@@ -184,7 +184,7 @@ PRIVATE int check_snapshot_index(struct data_store *dsp, int index)
 /*===========================================================================*
  *				check_sub_match				     *
  *===========================================================================*/
-PRIVATE int check_sub_match(struct subscription *subp,
+PRIVATE int check_sub_match(const struct subscription *subp,
 		struct data_store *dsp, endpoint_t ep)
 {
 /* Check if an entry matches a subscription. Return 1 in case of match. */
@@ -227,7 +227,7 @@ PRIVATE void update_subscribers(struct data_store *dsp, int set)
 /*===========================================================================*
  *		               map_service                                   *
  *===========================================================================*/
-PRIVATE int map_service(struct rprocpub *rpub)
+PRIVATE int map_service(const struct rprocpub *rpub)
 {
 /* Map a new service by registering its label. */
   struct data_store *dsp;
@@ -489,7 +489,7 @@ PUBLIC int do_retrieve(message *m_ptr)
 /*===========================================================================*
  *				do_retrieve_label			     *
  *===========================================================================*/
-PUBLIC int do_retrieve_label(message *m_ptr)
+PUBLIC int do_retrieve_label(const message *m_ptr)
 {
   struct data_store *dsp;
   int r;
@@ -743,7 +743,7 @@ PUBLIC int do_snapshot(message *m_ptr)
 /*===========================================================================*
  *				do_getsysinfo				     *
  *===========================================================================*/
-PUBLIC int do_getsysinfo(message *m_ptr)
+PUBLIC int do_getsysinfo(const message *m_ptr)
 {
   vir_bytes src_addr;
   size_t length;
diff --git a/servers/mfs/link.c b/servers/mfs/link.c
index 28939ddad..861854865 100644
--- a/servers/mfs/link.c
+++ b/servers/mfs/link.c
@@ -286,7 +286,6 @@ PUBLIC int fs_rename()
   char old_name[NAME_MAX], new_name[NAME_MAX];
   ino_t numb;
   phys_bytes len;
-  int r1;
   
   /* Copy the last component of the old name */
   len = MFS_MIN(fs_m_in.REQ_REN_LEN_OLD, sizeof(old_name));
diff --git a/servers/rs/manager.c b/servers/rs/manager.c
index 157097a1f..37a40fd25 100644
--- a/servers/rs/manager.c
+++ b/servers/rs/manager.c
@@ -1631,7 +1631,7 @@ struct priv *privp;
 	struct rprocpub *tmp_rpub;
 	endpoint_t endpoint;
 	int r;
-	int slot_nr, priv_id;
+	int priv_id;
 	struct priv priv;
 	struct rprocpub *rpub;
 
diff --git a/servers/rs/service/service.c b/servers/rs/service/service.c
index 1664f69be..baeeec82a 100644
--- a/servers/rs/service/service.c
+++ b/servers/rs/service/service.c
@@ -536,7 +536,6 @@ PRIVATE void do_irq(config_t *cpe)
 
 PRIVATE void do_io(config_t *cpe)
 {
-	int irq;
 	unsigned base, len;
 	char *check;
 
@@ -665,9 +664,6 @@ PRIVATE void do_pci_class(config_t *cpe)
 
 PRIVATE void do_pci(config_t *cpe)
 {
-	int i, call_nr, word, bits_per_word;
-	unsigned long mask;
-
 	if (cpe == NULL)
 		return;	/* Empty PCI statement */
 
@@ -811,7 +807,7 @@ PRIVATE void do_vm(config_t *cpe)
 
 PRIVATE void do_system(config_t *cpe)
 {
-	int i, call_nr;
+	int i;
 
 	/* Process a list of 'system' calls that are allowed */
 	for (; cpe; cpe= cpe->next)
@@ -1017,7 +1013,6 @@ PUBLIC int main(int argc, char **argv)
   message m;
   int result = EXIT_SUCCESS;
   int request;
-  int i;
   char *progname = NULL;
   struct passwd *pw;
 
diff --git a/servers/vfs/device.c b/servers/vfs/device.c
index 8c105e555..2407a2ef3 100644
--- a/servers/vfs/device.c
+++ b/servers/vfs/device.c
@@ -771,7 +771,6 @@ int flags;			/* mode bits and flags */
   if (op == DEV_OPEN && dev_mess.REP_STATUS >= 0) {
 	if (dev_mess.REP_STATUS != minor) {
                 struct vnode *vp;
-                struct vmnt *vmp;
                 struct node_details res;
 
 		/* A new minor device number has been returned.
@@ -873,7 +872,6 @@ PUBLIC void dev_up(int maj)
   needs_reopen= FALSE;
   for (fp = filp; fp < &filp[NR_FILPS]; fp++) {
 	struct vnode *vp;
-	int minor;
 
 	if(fp->filp_count < 1 || !(vp = fp->filp_vno)) continue;
 	if(((vp->v_sdev >> MAJOR) & BYTE) != maj) continue;
diff --git a/servers/vfs/request.c b/servers/vfs/request.c
index 9b0993e06..733bbdf1d 100644
--- a/servers/vfs/request.c
+++ b/servers/vfs/request.c
@@ -526,7 +526,6 @@ PUBLIC int req_mountpoint(fs_e, inode_nr)
 endpoint_t fs_e;
 ino_t inode_nr;
 {
-  int r;
   message m;
 
   /* Fill in request message */
@@ -1023,7 +1022,7 @@ PRIVATE int fs_sendrec_f(char *file, int line, endpoint_t fs_e, message *reqm)
  * It also handles driver recovery mechanism and reissuing the
  * request which failed due to a dead driver.
  */
-  int r, old_driver_e, new_driver_e;
+  int r, old_driver_e;
   message origm, m;
 
   if(fs_e <= 0 || fs_e == NONE)