diff options
Diffstat (limited to 'src/dd.c')
-rw-r--r-- | src/dd.c | 23 |
1 files changed, 22 insertions, 1 deletions
@@ -392,6 +392,25 @@ static char const ebcdic_to_ascii[] = '\070', '\071', '\372', '\373', '\374', '\375', '\376', '\377' }; +/* True if we need to close the standard output *stream*. */ +static bool close_stdout_required = true; + +/* The only reason to close the standard output *stream* is if + parse_long_options fails (as it does for --help or --version). + In any other case, dd uses only the STDOUT_FILENO file descriptor, + and the "cleanup" function calls "close (STDOUT_FILENO)". + Closing the file descriptor and then letting the usual atexit-run + close_stdout function call "fclose (stdout)" would result in a + harmless failure of the close syscall (with errno EBADF). + This function serves solely to avoid the unnecessary close_stdout + call, once parse_long_options has succeeded. */ +static void +maybe_close_stdout (void) +{ + if (close_stdout_required) + close_stdout (); +} + void usage (int status) { @@ -1655,12 +1674,14 @@ main (int argc, char **argv) textdomain (PACKAGE); /* Arrange to close stdout if parse_long_options exits. */ - atexit (close_stdout); + atexit (maybe_close_stdout); page_size = getpagesize (); parse_long_options (argc, argv, PROGRAM_NAME, PACKAGE, VERSION, usage, AUTHORS, (char const *) NULL); + close_stdout_required = false; + if (getopt_long (argc, argv, "", NULL, NULL) != -1) usage (EXIT_FAILURE); |