int spawn(char *program, char *argv[], int sin, int sout, int serr,
int search, char *envp[], char *pty_name, int wait)
{
pid_t pid;
int fd;
int channel[2];
sigset_t sset;
channel[0] = -1;
channel[1] = -1;
if (!pipe(channel)) {
if (-1==fcntl(channel[1], F_SETFD, FD_CLOEXEC)) {
close(channel[1]);
channel[1] = -1;
}
}
pid = fork();
if (pid) {
if ((-1 != pid) && (-1 != channel[1])) {
int child_errno = 0;
int bytes = sizeof(int);
int n;
char *p = (char*)&child_errno;
close(channel[1]);
/* Try to read child errno from channel. */
while ((bytes > 0) &&
(n = read(channel[0], p, bytes))) {
if (-1 == n) {
if (EINTR == errno) {
continue;
} else {
break;
}
} else {
bytes -= n;
p += n;
}
}
close(channel[0]);
if (child_errno) {
waitpid(pid, NULL, 0);
/* Our convention to tell Lisp that it was the exec that
* failed, not the fork. */
pid = -2;
errno = child_errno;
}
}
return pid;
}
close (channel[0]);
/* Put us in our own process group, but only if we need not
* share stdin with our parent. In the latter case we claim
* control of the terminal. */
if (sin >= 0) {
#if defined(LISP_FEATURE_HPUX) || defined(LISP_FEATURE_OPENBSD)
setsid();
#elif defined(LISP_FEATURE_DARWIN)
setpgid(0, getpid());
#elif defined(SVR4) || defined(__linux__) || defined(__osf__)
setpgrp();
#else
setpgrp(0, getpid());
#endif
} else {
tcsetpgrp(0, getpgrp());
}
/* unblock signals */
sigemptyset(&sset);
sigprocmask(SIG_SETMASK, &sset, NULL);
/* If we are supposed to be part of some other pty, go for it. */
if (pty_name)
set_pty(pty_name);
else {
/* Set up stdin, stdout, and stderr */
if (sin >= 0)
dup2(sin, 0);
if (sout >= 0)
dup2(sout, 1);
if (serr >= 0)
dup2(serr, 2);
}
/* Close all other fds. */
#ifdef SVR4
for (fd = sysconf(_SC_OPEN_MAX)-1; fd >= 3; fd--)
if (fd != channel[1]) close(fd);
#else
for (fd = getdtablesize()-1; fd >= 3; fd--)
if (fd != channel[1]) close(fd);
#endif
if (envp) {
environ = envp;
}
/* Exec the program. */
if (search)
execvp(program, argv);
else
execv(program, argv);
/* When exec fails and channel is available, send the errno value. */
if (-1 != channel[1]) {
int our_errno = errno;
int bytes = sizeof(int);
int n;
char *p = (char*)&our_errno;
while ((bytes > 0) &&
(n = write(channel[1], p, bytes))) {
if (-1 == n) {
if (EINTR == errno) {
continue;
} else {
break;
}
} else {
bytes -= n;
p += n;
}
}
close(channel[1]);
}
_exit(1);
}
int spawn(char *program, char *argv[], int sin, int sout, int serr,
int search, char *envp[], char *pty_name, int wait)
{
int pid = fork();
int fd;
sigset_t sset;
if (pid != 0)
return pid;
/* Put us in our own process group, but only if we need not
* share stdin with our parent. In the latter case we claim
* control of the terminal. */
if (sin >= 0) {
#if defined(LISP_FEATURE_HPUX) || defined(LISP_FEATURE_OPENBSD)
setsid();
#elif defined(LISP_FEATURE_DARWIN)
setpgid(0, getpid());
#elif defined(SVR4) || defined(__linux__) || defined(__osf__)
setpgrp();
#else
setpgrp(0, getpid());
#endif
} else {
tcsetpgrp(0, getpgrp());
}
/* unblock signals */
sigemptyset(&sset);
sigprocmask(SIG_SETMASK, &sset, NULL);
/* If we are supposed to be part of some other pty, go for it. */
if (pty_name)
set_pty(pty_name);
else {
/* Set up stdin, stdout, and stderr */
if (sin >= 0)
dup2(sin, 0);
if (sout >= 0)
dup2(sout, 1);
if (serr >= 0)
dup2(serr, 2);
}
/* Close all other fds. */
#ifdef SVR4
for (fd = sysconf(_SC_OPEN_MAX)-1; fd >= 3; fd--)
close(fd);
#else
for (fd = getdtablesize()-1; fd >= 3; fd--)
close(fd);
#endif
environ = envp;
/* Exec the program. */
if (search)
execvp(program, argv);
else
execv(program, argv);
exit (1);
}
