- pull r15578 from busybox_scratch branch:

  - fix bug where it would behave wrong if ./nohup.out was not writable.
  - debloat and make it readable while at it.
$ size coreutils/nohup.o*
   text    data     bss     dec     hex filename
    362       0       0     362     16a coreutils/nohup.o.trunk
    344       0       0     344     158 coreutils/nohup.o
$ make bloatcheck
function                                             old     new   delta
nohup_main                                           324     310     -14
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-14)             Total: -14 bytes

1 files changed, 21 insertions, 25 deletions

diff --git a/coreutils/nohup.c b/coreutils/nohup.c
index 9e9150d33..cf8ad2cd4 100644
--- a/coreutils/nohup.c
+++ b/coreutils/nohup.c
@@ -5,53 +5,49 @@
  * http://www.opengroup.org/onlinepubs/007904975/utilities/nohup.html
  *
  * Copyright 2006 Rob Landley <rob@landley.net>
+ * Copyright 2006 Bernhard Fischer
  *
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
 #include "busybox.h"
 
-int nohup_main(int argc, char *argv[])
+int nohup_main(int argc, char **argv)
 {
 	int temp, nullfd;
-	char *nohupout = "nohup.out", *home = NULL;
-
-	// I have no idea why the standard cares about this.
+	char *nohupout, *home = NULL;
 
 	bb_default_error_retval = 127;
 
 	if (argc<2) bb_show_usage();
 
 	nullfd = xopen(bb_dev_null, O_WRONLY|O_APPEND);
-	// If stdin is a tty, detach from it.
-
-	if (isatty(0)) dup2(nullfd, 0);
-
-	// Redirect stdout to nohup.out, either in "." or in "$HOME".
+	/* If stdin is a tty, detach from it. */
+	if (isatty(STDIN_FILENO)) dup2(nullfd, STDIN_FILENO);
 
-	if (isatty(1)) {
-		close(1);
+	nohupout = "nohup.out";
+	/* Redirect stdout to nohup.out, either in "." or in "$HOME". */
+	if (isatty(STDOUT_FILENO)) {
+		close(STDOUT_FILENO);
 		if (open(nohupout, O_CREAT|O_WRONLY|O_APPEND, S_IRUSR|S_IWUSR) < 0) {
 			home = getenv("HOME");
 			if (home) {
-				home = concat_path_file(home, nohupout);
+				nohupout = concat_path_file(home, nohupout);
 				xopen3(nohupout, O_CREAT|O_WRONLY|O_APPEND, S_IRUSR|S_IWUSR);
 			}
 		}
-	} else dup2(nullfd, 1);
-
-	// If we have a tty on strderr, announce filename and redirect to stdout.
-	// Else redirect to /dev/null.
-
-	temp = isatty(2);
-	if (temp) fdprintf(2,"Writing to %s\n", home ? home : nohupout);
-	dup2(temp ? 1 : nullfd, 2);
+	} else dup2(nullfd, STDOUT_FILENO);
+
+	/* If we have a tty on strderr, announce filename and redirect to stdout.
+	 * Else redirect to /dev/null.
+	 */
+	temp = isatty(STDERR_FILENO);
+	if (temp) bb_error_msg("Appending to %s", nohupout);
+	dup2(temp ? STDOUT_FILENO : nullfd, STDERR_FILENO);
 	close(nullfd);
-	signal(SIGHUP, SIG_IGN);
-
-	// Exec our new program.
+	signal (SIGHUP, SIG_IGN);
 
 	execvp(argv[1],argv+1);
-	if (ENABLE_FEATURE_CLEAN_UP) free(home);
-	bb_error_msg_and_die("exec %s",argv[1]);
+	if (00 && ENABLE_FEATURE_CLEAN_UP && home) free(nohupout);
+	bb_perror_msg_and_die("%s",argv[1]);
 }