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/* Asynchronous processes using ptys */
/* Copyright (c) 1992, 1995 John E. Davis
* All rights reserved.
*
* You may distribute under the terms of either the GNU General Public
* License or the Perl Artistic License.
*/
#ifdef HAS_SUBPROCESSES
#include "config.h"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <fcntl.h>
#include <signal.h>
#include <unistd.h>
#include "slang.h"
#include "_slang.h"
#include "slfile.h"
/* On ultrix, pseudo terminals are named /dev/tty?? and /dev/pty??
where ?? is [pq][0-9a-f] */
static char PTY_Name[80], TTY_Name[80];
int open_pty ()
{
int ft, fp;
char *p, *t, *p1, *t1;
char *list1 = "pq", *list2 = "0123456789abcdef";
strcpy (PTY_Name, "/dev/pty");
strcpy (TTY_Name, "/dev/tty");
p = PTY_Name + strlen (PTY_Name); t = TTY_Name + strlen (TTY_Name);
for (p1 = list1; *p1 != 0; p1++)
{
*p++ = *p1; *t++ = *p1;
for (t1 = list2; *t1 != 0; t1++)
{
*p++ = *t1; *p = 0;
*t++ = *t1; *t = 0;
if ((fp = open (PTY_Name, O_RDWR)) >= 0)
{
if ((ft = open (TTY_Name, O_RDWR)) >= 0)
{
close (ft);
return fp;
}
close (fp);
}
t--; p--;
}
t--; p--;
}
return -1;
}
int child_code (char *name)
{
execl (name, NULL);
exit(0);
}
/* returns the child pid upon success or -1 upon error. */
static int create_process (char *name, int *fd)
{
int child_pid;
int ft;
*fd = open_pty();
if (*fd < 0) return -1;
if (fcntl (*fd, F_SETFL, O_NDELAY) < 0)
{
fprintf(stderr, "fcntl 1 failed.\n");
}
if (0 == (child_pid = fork()))
{
setsid ();
if ((ft = open (TTY_Name, O_RDWR)) < 0)
{
fprintf(stderr, "Child: unable to open tty");
}
dup2(ft, fileno(stderr));
dup2(ft, fileno(stdout));
dup2(ft, fileno(stdin));
child_code (name);
}
return child_pid;
}
void child_signal(int sig)
{
}
int SLcreate_child_process (char *name)
{
SL_File_Table_Type *t;
FILE *fp;
int fd, pid;
if ((t = get_file_table_entry()) == NULL) return (-1);
if (-1 == (pid = create_process (name, &fd))) return -1;
signal (SIGCHLD, child_signal);
if ((fp = fdopen (fd, "r+")) == NULL)
{
close (fd);
return -1;
}
t->fp = fp;
t->fd = fd;
t->flags = SL_WRITE | SL_READ | SL_PROCESS;
t->pid = pid;
SLang_push_integer (pid);
return ((int) (t - SL_File_Table));
}
#endif /* HAS_SUBPROCESSES */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.