--- /dev/null
+/* Test of posix_spawn() function with 'open' action and O_APPEND flag.
+ Copyright (C) 2008-2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2020. */
+
+/* Test whether posix_spawn_file_actions_addopen supports the O_APPEND flag. */
+
+#include <config.h>
+
+#include <spawn.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#define CHILD_PROGRAM_FILENAME "test-posix_spawn-open2"
+#define DATA_FILENAME "test-posix_spawn-open2-data.tmp"
+
+static int
+parent_main (void)
+{
+ FILE *fp;
+ char *argv[3] = { CHILD_PROGRAM_FILENAME, "-child", NULL };
+ posix_spawn_file_actions_t actions;
+ bool actions_allocated;
+ int err;
+ pid_t child;
+ int status;
+ int exitstatus;
+
+ /* Create a data file with specific contents. */
+ fp = fopen (DATA_FILENAME, "wb");
+ if (fp == NULL)
+ {
+ perror ("cannot create data file");
+ return 1;
+ }
+ fwrite ("Halle ", 1, 6, fp);
+ if (fflush (fp) || fclose (fp))
+ {
+ perror ("cannot prepare data file");
+ return 1;
+ }
+
+ /* Test whether posix_spawn_file_actions_addopen with O_APPEND flag causes
+ the child to append to this file. */
+ actions_allocated = false;
+ if ((err = posix_spawn_file_actions_init (&actions)) != 0
+ || (actions_allocated = true,
+ (err = posix_spawn_file_actions_addopen (&actions, STDOUT_FILENO, DATA_FILENAME, O_RDWR | O_APPEND, 0600)) != 0
+ || (err = posix_spawn (&child, CHILD_PROGRAM_FILENAME, &actions, NULL, argv, environ)) != 0))
+ {
+ if (actions_allocated)
+ posix_spawn_file_actions_destroy (&actions);
+ errno = err;
+ perror ("subprocess failed");
+ return 1;
+ }
+ posix_spawn_file_actions_destroy (&actions);
+ status = 0;
+ while (waitpid (child, &status, 0) != child)
+ ;
+ if (!WIFEXITED (status))
+ {
+ fprintf (stderr, "subprocess terminated with unexpected wait status %d\n", status);
+ return 1;
+ }
+ exitstatus = WEXITSTATUS (status);
+ if (exitstatus != 0)
+ {
+ fprintf (stderr, "subprocess terminated with unexpected exit status %d\n", exitstatus);
+ return 1;
+ }
+
+ /* Check the contents of the data file. */
+ fp = fopen (DATA_FILENAME, "rb");
+ if (fp == NULL)
+ {
+ perror ("cannot open data file");
+ return 1;
+ }
+ char buf[1024];
+ int nread = fread (buf, 1, sizeof (buf), fp);
+ if (!(nread == 11 && memcmp (buf, "Halle Potta", 11) == 0))
+ {
+ fprintf (stderr, "data file wrong: has %d bytes, expected %d bytes\n", nread, 11);
+ return 1;
+ }
+ if (fclose (fp))
+ {
+ perror ("cannot close data file");
+ return 1;
+ }
+
+ /* Clean up data file. */
+ unlink (DATA_FILENAME);
+
+ return 0;
+}
+
+static int
+child_main (void)
+{
+ /* Write to STDOUT_FILENO. */
+ fwrite ("Potta", 1, 5, stdout);
+ /* No 'fflush (stdout);' is needed. It is implicit when the child process
+ exits. */
+
+ return 0;
+}
+
+static void
+cleanup_then_die (int sig)
+{
+ /* Clean up data file. */
+ unlink (DATA_FILENAME);
+
+ /* Re-raise the signal and die from it. */
+ signal (sig, SIG_DFL);
+ raise (sig);
+}
+
+int
+main (int argc, char *argv[])
+{
+ int exitstatus;
+
+ if (!(argc > 1 && strcmp (argv[1], "-child") == 0))
+ {
+ /* This is the parent process. */
+ signal (SIGINT, cleanup_then_die);
+ signal (SIGTERM, cleanup_then_die);
+ #ifdef SIGHUP
+ signal (SIGHUP, cleanup_then_die);
+ #endif
+
+ exitstatus = parent_main ();
+ }
+ else
+ {
+ /* This is the child process. */
+ exitstatus = child_main ();
+ }
+ return exitstatus;
+}