--- /dev/null
+.\" $NetBSD: from.1,v 1.8 2003/08/07 11:13:49 agc Exp $
+.\"
+.\" Copyright (c) 1980, 1990, 1993
+.\" The Regents of the University of California. All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in the
+.\" documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)from.1 8.2 (Berkeley) 12/30/93
+.\"
+.Dd December 30, 1993
+.Dt FROM 1
+.Os
+.Sh NAME
+.Nm from
+.Nd print names of those who have sent mail
+.Sh SYNOPSIS
+.Nm
+.Op Fl s Ar sender
+.Op Fl f Ar file
+.Op Ar user
+.Sh DESCRIPTION
+.Nm
+prints
+out the mail header lines from the invoker's mailbox.
+.Pp
+Options:
+.Bl -tag -width Fl
+.It Fl f Ar file
+The supplied file
+is examined instead of the invoker's mailbox.
+If the
+.Fl f
+option is used, the
+.Ar user
+argument should not be used.
+.It Fl s Ar sender
+Only mail from addresses containing
+the
+supplied string are printed.
+.El
+.Pp
+If
+.Ar user
+is given, the
+.Ar user Ns 's
+mailbox, is examined instead of the invoker's own mailbox.
+(Privileges are required.)
+.Sh FILES
+.Bl -tag -width /var/mail/* -compact
+.It Pa /var/mail/*
+.El
+.Sh SEE ALSO
+.Xr biff 1 ,
+.Xr mail 1
+.Sh HISTORY
+The
+.Nm
+command appeared in
+.Bx 3.0 .
--- /dev/null
+/* $NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $ */
+
+/*
+ * Copyright (c) 1980, 1988, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#ifndef lint
+__COPYRIGHT("@(#) Copyright (c) 1980, 1988, 1993\
+ The Regents of the University of California. All rights reserved.");
+#endif /* not lint */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)from.c 8.1 (Berkeley) 6/6/93";
+#endif
+__RCSID("$NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $");
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <ctype.h>
+#include <err.h>
+#include <paths.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+int main (int, char **);
+int match (const char *, const char *);
+
+int
+main(int argc, char **argv)
+{
+ struct passwd *pwd;
+ int ch, newline;
+ char *file, *sender, *p;
+#if MAXPATHLEN > BUFSIZ
+ char buf[MAXPATHLEN];
+#else
+ char buf[BUFSIZ];
+#endif
+
+ file = sender = NULL;
+ while ((ch = getopt(argc, argv, "f:s:")) != -1)
+ switch((char)ch) {
+ case 'f':
+ file = optarg;
+ break;
+ case 's':
+ sender = optarg;
+ for (p = sender; *p; ++p)
+ *p = tolower((unsigned char)*p);
+ break;
+ default:
+ fprintf(stderr, "usage: from [-f file] [-s sender] [user]\n");
+ exit(1);
+ }
+ argv += optind;
+
+ /*
+ * We find the mailbox by:
+ * 1 -f flag
+ * 2 user
+ * 2 MAIL environment variable
+ * 3 _PATH_MAILDIR/file
+ */
+ if (!file) {
+ if (!(file = *argv)) {
+ if (!(file = getenv("MAIL"))) {
+ if (!(pwd = getpwuid(getuid())))
+ errx(1, "no password file entry for you");
+ if ((file = getenv("LOGNAME")) != NULL ||
+ (file = getenv("USER")) != NULL) {
+ (void)snprintf(buf, sizeof(buf),
+ "%s/%s", _PATH_MAILDIR, file);
+ file = buf;
+ } else
+ (void)snprintf(file = buf, sizeof(buf),
+ "%s/%s",
+ _PATH_MAILDIR, pwd->pw_name);
+ }
+ } else {
+ (void)snprintf(buf, sizeof(buf), "%s/%s",
+ _PATH_MAILDIR, file);
+ file = buf;
+ }
+ }
+ if (!freopen(file, "r", stdin))
+ err(1, "can't read %s", file);
+
+ for (newline = 1; fgets(buf, sizeof(buf), stdin);) {
+ if (*buf == '\n') {
+ newline = 1;
+ continue;
+ }
+ if (newline && !strncmp(buf, "From ", 5) &&
+ (!sender || match(buf + 5, sender)))
+ printf("%s", buf);
+ newline = 0;
+ }
+ exit(0);
+}
+
+int
+match(const char *line, const char *sender)
+{
+ char ch, pch, first;
+ const char *p, *t;
+
+ for (first = *sender++;;) {
+ if (isspace((unsigned char)(ch = *line)))
+ return(0);
+ ++line;
+ ch = tolower((unsigned char)ch);
+ if (ch != first)
+ continue;
+ for (p = sender, t = line;;) {
+ if (!(pch = *p++))
+ return(1);
+ ch = tolower((unsigned char)*t++);
+ if (ch != pch)
+ break;
+ }
+ }
+ /* NOTREACHED */
+}