[RFC PATCH 1/1] add --stderr option

[Tomi Ollila <tomi.ollila@iki.fi>]

---

Note quickly written untested code (but compiles!), just to show an idea...

This implements (i hope) curl(1) --stderr option in notmuch(1):

       --stderr <file>
              Redirect  all writes to stderr to the specified file instead. If
              the file name is a plain '-', it is instead written to stdout.

This would be useful in emacs interface.

Please comment; I'll do help and manual page changes (and NEWS) if
this is good idea :D

Tomi


 notmuch.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/notmuch.c b/notmuch.c
index f51a84f..3b8bd5d 100644
--- a/notmuch.c
+++ b/notmuch.c
@@ -21,6 +21,7 @@
  */
 
 #include "notmuch-client.h"
+#include <fcntl.h>
 
 typedef int (*command_function_t) (notmuch_config_t *config, int argc, char *argv[]);
 
@@ -259,6 +260,7 @@ main (int argc, char *argv[])
     const char *command_name = NULL;
     command_t *command;
     char *config_file_name = NULL;
+    char *stderr_file = NULL;
     notmuch_config_t *config;
     notmuch_bool_t print_help=FALSE, print_version=FALSE;
     int opt_index;
@@ -268,6 +270,7 @@ main (int argc, char *argv[])
 	{ NOTMUCH_OPT_BOOLEAN, &print_help, "help", 'h', 0 },
 	{ NOTMUCH_OPT_BOOLEAN, &print_version, "version", 'v', 0 },
 	{ NOTMUCH_OPT_STRING, &config_file_name, "config", 'c', 0 },
+	{ NOTMUCH_OPT_STRING, &stderr_file, "stderr", 'c', 0 },
 	{ 0, 0, 0, 0, 0 }
     };
 
@@ -295,6 +298,23 @@ main (int argc, char *argv[])
 	return 0;
     }
 
+    if (stderr_file) {
+	if (strcmp (stderr_file, "-") == 0)
+	    dup2 (STDOUT_FILENO, STDERR_FILENO);
+	else {
+	    int fd = open (stderr_file, O_WRONLY|O_CREAT|O_APPEND, 0644);
+	    if (fd < 0) {
+		fprintf (stderr, "Error: Cannot redirect stderr to '%s': %s\n",
+			 stderr_file, strerror(errno));
+		return 1;
+	    }
+	    if (fd != STDERR_FILENO) {
+		dup2 (fd, STDERR_FILENO);
+		close (fd);
+	    }
+	}
+    }
+
     if (opt_index < argc)
 	command_name = argv[opt_index];
 
-- 
1.8.1.4