mail back errors (perhaps this is why mail gets lost.....)

[unix-history] / usr / src / bin / rmail / rmail.c

/*
* rmail: front end for mail to stack up those stupid >From ... remote from ...
* lines and make a correct return address.  This works with the -f option
* to /usr/lib/sendmail so it won't work on systems without sendmail.
* However, it ought to be easy to modify a standard /bin/mail to do the
* same thing.
*
* NOTE: Rmail is SPECIFICALLY INTENDED for ERNIE COVAX because of its
* physical position as a gateway between the uucp net and the arpanet.
* By default, other sites will probably want /bin/rmail to be a link
* to /bin/mail, as it was intended by BTL.  However, other than the
* (somewhat annoying) loss of information about when the mail was
* originally sent, rmail should work OK on other systems running uucp.
* If you don't run uucp you don't even need any rmail.
*/

static char     SccsId[] =      "@(#)rmail.c    3.2     %G%";

# include <stdio.h>
# include <sysexits.h>
# include "useful.h"

extern FILE *popen();
extern char *index();

bool    Debug;

# define MAILER "/usr/lib/sendmail"

main(argc, argv)
       char **argv;
{
       FILE *out;      /* output to sendmail */
       char lbuf[512]; /* one line of the message */
       char from[512]; /* accumulated path of sender */
       char ufrom[64]; /* user on remote system */
       char sys[64];   /* a system in path */
       char junk[512]; /* scratchpad */
       char cmd[2000];
       register char *cp;

# ifdef DEBUG
       if (argc > 1 && strcmp(argv[1], "-T") == 0)
       {
               Debug = TRUE;
               argc--;
               argv++;
       }
# endif DEBUG

       if (argc < 2)
       {
               fprintf(stderr, "Usage: rmail user ...\n");
               exit(EX_USAGE);
       }

       for (;;)
       {
               fgets(lbuf, sizeof lbuf, stdin);
               if (strncmp(lbuf, "From ", 5) != 0 && strncmp(lbuf, ">From ", 6) != 0)
                       break;
               sscanf(lbuf, "%s %s", junk, ufrom);
               cp = lbuf;
               for (;;)
               {
                       cp = index(cp+1, 'r');
                       if (cp == NULL)
                               cp = "remote from somewhere";
#ifdef DEBUG
                       if (Debug)
                               printf("cp='%s'\n", cp);
#endif
                       if (strncmp(cp, "remote from ", 12)==0)
                               break;
               }
               sscanf(cp, "remote from %s", sys);
               strcat(from, sys);
               strcat(from, "!");
#ifdef DEBUG
               if (Debug)
                       printf("ufrom='%s', sys='%s', from now '%s'\n", ufrom, sys, from);
#endif
       }
       strcat(from, ufrom);

       sprintf(cmd, "%s -em -f%s", MAILER, from);
       while (*++argv != NULL)
       {
               strcat(cmd, " '");
               strcat(cmd, *argv);
               strcat(cmd, "'");
       }
#ifdef DEBUG
       if (Debug)
               printf("cmd='%s'\n", cmd);
#endif
       out = popen(cmd, "w");
       fputs(lbuf, out);
       while (fgets(lbuf, sizeof lbuf, stdin))
               fputs(lbuf, out);
       pclose(out);

       exit(EX_OK);
}