* child_info.h (child_info_spawn::__stdin): New element.

(child_info_spawn::__stdin): Ditto.
(CURR_CHILD_INFO_MAGIC): Regenerate.
* dcrt0.cc (check_sanity_and_sync): Minor cleanup.
(child_info_spawn::handle_spawn): Handle new __std* elements by calling
move_fd.
* dtable.cc (dtable::move_fd): Define new function.
* dtable.h (dtable::move_fd): Declare new function.
* fhandler.h (fhandler_pipe::popen_pid): Declare new element.
* fhandler.h (fhandler_pipe::get_popen_pid): Define new function.
* fhandler.h (fhandler_pipe::set_popen_pid): Ditto.
* pipe.cc (fhandler_pipe::fhandler_pipe): Zero popen_pid.
(fhandler_pipe::dup): Ditto.
* spawn.cc (handle): Change second argument to bool.
(spawn_guts): Accept __stdin/__stdout arguments and set them appropriately in
child_info structure and in STARTUPINFO structure.
* syscalls.cc (popen): New cygwin-specific implementation using spawn.
(pclose): Ditto.
* winsup.h (spawn_guts): Accommodate new arguments for spawn_guts.
* fhandler.cc (fhandler_base::set_no_inheritance): Make second arg a bool.
* fhandler.h (fhandler_base::set_no_inheritance): Ditto for declaration.
* child_info.h (child_info::msv_count): Rename from the now-inappropriate
"zero".
(child_info_spawn::filler): Add filler to work around Vista bug.
(child_info_fork::filler): Ditto.
* dcrt0.cc (get_cygwin_startup_info): Remove "zero" check since it is now
always filled out.
* fork.cc (frok::parent): Move ch.zero manipulation to constructor.
* spawn.cc (spawn_guts): Ditto.  Remove _ch wrapper.
* sigproc.cc (child_info::child_info): Initialize starter[].
* shared.cc (shared_info::heap_slop_size): Remove noisy system_printfs.
* shared_info.h (CURR_SHARED_MAGIC): Regenerate.

winsup/cygwin/syscalls.cc

@@ -40,6 +40,7 @@ details. */
 #include <limits.h>
 #include <unistd.h>
 #include <setjmp.h>
+#include <sys/wait.h>
 #include <winnls.h>
 #include <wininet.h>
 #include <winioctl.h>
@@ -3242,3 +3243,109 @@ funlockfile (FILE *file)
 {
   _funlockfile (file);
 }
+
+extern "C" FILE *
+popen (const char *command, const char *type)
+{
+  int fds[2];
+
+  if (pipe (fds) < 0)
+    return NULL;
+  int fd, other_fd, __stdin, __stdout, stdwhat;
+  if (type[1] != '\0')
+    {
+      set_errno (EINVAL);
+      return NULL;
+    }
+  if (*type == 'r')
+    {
+      __stdin = -1;
+      stdwhat = 1;
+      other_fd = __stdout = fds[1];
+      fd = fds[0];
+    }
+  else if (*type == 'w')
+    {
+      __stdout = -1;
+      stdwhat = 0;
+      other_fd = __stdin = fds[0];
+      fd = fds[1];
+    }
+  else
+    {
+      set_errno (EINVAL);
+      return NULL;
+    }
+
+  FILE *fp = fdopen (fd, type);
+  fcntl (fd, F_SETFD, fcntl (fd, F_GETFD, 0) | FD_CLOEXEC);
+
+  if (!fp)
+    goto err;
+
+  pid_t pid;
+  const char *argv[4];
+
+  argv[0] = "/bin/sh";
+  argv[1] = "-c";
+  argv[2] = command;
+  argv[3] = NULL;
+
+  {
+    lock_process now;
+    int state = fcntl (stdwhat, F_GETFD, 0);
+    fcntl (stdwhat, F_SETFD, state | FD_CLOEXEC);
+    pid = spawn_guts ("/bin/sh", argv, cur_environ (), _P_NOWAIT,
+		      __stdin, __stdout);
+    fcntl (stdwhat, F_SETFD, state);
+  }
+
+  if (pid < 0)
+    goto err;
+  close (other_fd);
+
+  fhandler_pipe *fh = (fhandler_pipe *) cygheap->fdtab[fd];
+  fh->set_popen_pid (pid);
+
+  return fp;
+
+err:
+  int save_errno = get_errno ();
+  close (fds[0]);
+  close (fds[1]);
+  set_errno (save_errno);
+  return NULL;
+}
+
+int
+pclose (FILE *fp)
+{
+  fhandler_pipe *fh = (fhandler_pipe *) cygheap->fdtab[fileno(fp)];
+
+  if (fh->get_device () != FH_PIPEW && fh->get_device () != FH_PIPER)
+    {
+      set_errno (EBADF);
+      return -1;
+    }
+
+  int pid = fh->get_popen_pid ();
+  if (!pid)
+    {
+      set_errno (ECHILD);
+      return -1;
+    }
+
+  if (fclose (fp))
+    return -1;
+
+  int status;
+  while (1)
+    if (waitpid (pid, &status, 0) == pid)
+      break;
+    else if (get_errno () == EINTR)
+      continue;
+    else
+      return -1;
+
+  return status;
+}