gno/usr.bin/write/write.c
1998-04-10 19:50:41 +00:00

132 lines
3.1 KiB
C

/* write.cc - UNIX-like write utility. Send message to terminal. */
/* Copyright 1993 by Leslie M. Barstow III */
/* Placed in the Public Domain with the following condition:
Please retain original Copyright in source, program, and manpage. */
#pragma optimize -1
#pragma debug 0
#pragma stacksize 1024
#define O_WRONLY 0x0002
#include <time.h>
#include <types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <orca.h>
#include <utmp.h>
#include <fcntl.h>
void Usage(void)
{fputs("usage: write username [message]\n",stdout);
fputs("GS write: Copyright 1993 by Leslie M. Barstow III.\n", stdout);
}
int userTTY(char *user, int **list)
{int fd, tmp;
struct utmp uentry;
int count = 0;
int *newlist;
fd=open(_PATH_UTMP, 257);
if (fd < 1)
{fputs("write - unable to retrieve current users.\n", stdout);
exit(-1);
}
do
{tmp = read(fd, (void *)(&uentry), sizeof(uentry));
if (tmp)
{if (!strncmp(uentry.ut_name,user,strlen(user)))
{count++;
newlist = (int *)realloc(*list, count *2);
if (newlist == (int *)0L)
{for (tmp = 1; tmp < count; tmp++)
close((*list)[tmp-1]);
free(*list);
close(fd);
fputs("write - unable to allocate memory.\n", stdout);
exit(-1);
}
*list = newlist;
(*list)[count-1] = open(uentry.ut_line, 0x0002);
if ((*list)[count-1] < 1)
{fputs("write - unable to open terminal ",stdout);
fputs(uentry.ut_line, stdout);
fputs(".\n", stdout);
count--;
}
}
}
}
while (tmp);
close(fd);
return(count);
}
int main(int argc, char **argv)
{int count;
int i;
int j = 2;
char *line, *uname;
int *fdlist = (int *)0L;
if (argc > 3)
{Usage();
exit(-1);
}
if (argc == 3)
{count = userTTY(argv[1], &fdlist);
if (count < 1)
{fputs("write - no active terminals for user.\n", stdout);
exit(-1);
}
uname = getenv("user");
for (i = 0; i < count; i++)
{write(fdlist[i], "\n\aMessage from ", 15);
write(fdlist[i], uname, strlen(uname));
write(fdlist[i], ".\r\n", 3);
write(fdlist[i], argv[2], strlen(argv[2]));
write(fdlist[i], "\r\n", 2);
}
for (i = 0; i < count; i++)
close(fdlist[i]);
exit(0);
}
if ((argc == 2) && (argv[1][0] != '-')) /* enter read loop */
{line = (char *)malloc(256);
if (line == (char *)0L)
{fputs("write - error allocating buffer.\n", stdout);
exit(-1);
}
count = userTTY(argv[1], &fdlist);
if (count < 1)
{fputs("write - no active terminals for user.\n", stdout);
free(line);
exit(-1);
}
uname = getenv("user");
for(i = 0; i < count; i++)
{write(fdlist[i], "\n\aMessage from ", 15);
write(fdlist[i], uname, strlen(uname));
write(fdlist[i], ".\r\n", 3);
}
while (j > 1)
{fgets(line, 256, stdin);
j = strlen(line);
for (i = 0; i< count; i++)
write(fdlist[i], line, j);
}
free(line);
for (i = 0; i < count; i++)
close(fdlist[i]);
exit(0);
}
else
{Usage();
exit(-1);
}
}