Send help text to stdout rather than stderr.

This helps with piping to a pager for example.

diff --git a/mdadm.c b/mdadm.c
index 9bec29589c6291ae9af9e7df91df174f83c36e9a..e5ed93de4b1c6c88b98395387ba07c7a9e0aa9fe 100644 (file)
--- a/mdadm.c
+++ b/mdadm.c
@@ -106,6 +106,7 @@ int main(int argc, char *argv[])
 
        int copies;
        int print_help = 0;
+       FILE *outf;
 
        int mdfd = -1;
 
@@ -226,7 +227,7 @@ int main(int argc, char *argv[])
                        if (opt == 'c' && 
                            ( strncmp(optarg, "--h", 3)==0 ||
                              strncmp(optarg, "-h", 2)==0)) {
-                               fputs(Help_config, stderr);
+                               fputs(Help_config, stdout);
                                exit(0);
                        }
 
@@ -604,17 +605,24 @@ int main(int argc, char *argv[])
 
                                continue;
                        }
-                       if (strcmp(update,"?") == 0 || strcmp(update, "help") == 0)
-                               fprintf(stderr, Name ": ");
-                       else
-                               fprintf(stderr, Name ": '--update=%s' is invalid.  ", update);
-                       fprintf(stderr, "Valid --update options are:\n"
+                       if (strcmp(update,"?") == 0 ||
+                           strcmp(update, "help") == 0) {
+                               outf = stdout;
+                               fprintf(outf, Name ": ");
+                       } else {
+                               outf = stderr;
+                               fprintf(outf,
+                                       Name ": '--update=%s' is invalid.  ",
+                                       update);
+                       }
+                       fprintf(outf, "Valid --update options are:\n"
                "     'sparc2.2', 'super-minor', 'uuid', 'name', 'resync',\n"
                "     'summaries', 'homehost', 'byteorder', 'devicesize'.\n");
-                       exit(2);
+                       exit(outf == stdout ? 0 : 2);
 
                case O(ASSEMBLE,NoDegraded): /* --no-degraded */
-                       runstop = -1; /* --stop isn't allowed for --assemble, so we overload slightly */
+                       runstop = -1; /* --stop isn't allowed for --assemble,
+                                      * so we overload slightly */
                        continue;
 
                case O(ASSEMBLE,'c'): /* config file */
@@ -873,7 +881,7 @@ int main(int argc, char *argv[])
                        case GROW     : help_text = Help_grow; break;
                        case INCREMENTAL:help_text= Help_incr; break;
                        }
-               fputs(help_text,stderr);
+               fputs(help_text,stdout);
                exit(0);
        }