bringing back dd's noctty flag

[Paul Eggert]

I installed this, as it turns out it's needed for POSIX conformance:

2004-11-20  Paul Eggert  <address@hidden>

        Restore dd's noctty flag, reverting the change of 2004-04-08.
        POSIX does not allow "dd" to use O_NOCTTY by default.
        * NEWS: Add noctty flag to dd.
        * doc/coreutils.texi (dd invocation): Likewise.
        * src/dd.c (flags, usage, main): Likewise.

Index: NEWS
===================================================================
RCS file: /fetish/cu/NEWS,v
retrieving revision 1.250
diff -p -u -r1.250 NEWS
--- NEWS        16 Nov 2004 07:45:15 -0000      1.250
+++ NEWS        20 Nov 2004 08:46:17 -0000
@@ -200,6 +200,7 @@ GNU coreutils NEWS                      
     sync      likewise, but also for metadata
     nonblock  use non-blocking I/O
     nofollow  do not follow symlinks
+    noctty    do not assign controlling terminal from file
 
   stty now provides support (iutf8) for setting UTF-8 input mode.
 
Index: doc/coreutils.texi
===================================================================
RCS file: /fetish/cu/doc/coreutils.texi,v
retrieving revision 1.227
diff -p -u -r1.227 coreutils.texi
--- doc/coreutils.texi  16 Nov 2004 20:29:58 -0000      1.227
+++ doc/coreutils.texi  20 Nov 2004 08:46:20 -0000
@@ -6832,12 +6832,20 @@ Use non-blocking I/O.
 @cindex symbolic links, following
 Do not follow symbolic links.
 
address@hidden noctty
address@hidden noctty
address@hidden controlling terminal
+Do not assign the file to be a controlling terminal for @command{dd}.
+This has no effect when the file is not a terminal.
+On many hosts (e.g., @acronym{GNU}/Linux hosts), this option has no effect
+at all.
+
 @end table
 
 These flags are not supported on all systems, and @samp{dd} rejects
 attempts to use them when they are not supported.  When reading from
-standard input or writing to standard output, the @samp{nofollow} flag
-should not be specified, and the other flags
+standard input or writing to standard output, the @samp{nofollow} and
address@hidden flags should not be specified, and the other flags
 (e.g., @samp{nonblock}) can affect how other processes behave with the
 affected file descriptors, even after @command{dd} exits.
 
Index: src/dd.c
===================================================================
RCS file: /fetish/cu/src/dd.c,v
retrieving revision 1.170
diff -p -u -r1.170 dd.c
--- src/dd.c    17 Nov 2004 00:56:25 -0000      1.170
+++ src/dd.c    20 Nov 2004 08:46:20 -0000
@@ -230,6 +230,7 @@ static struct symbol_value const flags[]
   {"append",   O_APPEND},
   {"direct",   O_DIRECT},
   {"dsync",    O_DSYNC},
+  {"noctty",   O_NOCTTY},
   {"nofollow", O_NOFOLLOW},
   {"nonblock", O_NONBLOCK},
   {"sync",     O_SYNC},
@@ -431,6 +432,9 @@ Each FLAG symbol may be:\n\
        fputs (_("  nonblock  use non-blocking I/O\n"), stdout);
       if (O_NOFOLLOW)
        fputs (_("  nofollow  do not follow symlinks\n"), stdout);
+      if (O_NOCTTY)
+       fputs (_("  noctty    do not assign controlling terminal from file\n"),
+              stdout);
       fputs (_("\
 \n\
 Sending a SIGUSR1 signal to a running `dd' process makes it\n\
@@ -1469,8 +1473,7 @@ main (int argc, char **argv)
     }
   else
     {
-      int opts = input_flags | O_NOCTTY;
-      if (open_fd (STDIN_FILENO, input_file, O_RDONLY | opts, 0) < 0)
+      if (open_fd (STDIN_FILENO, input_file, O_RDONLY | input_flags, 0) < 0)
        error (EXIT_FAILURE, errno, _("opening %s"), quote (input_file));
     }
 
@@ -1488,7 +1491,7 @@ main (int argc, char **argv)
     {
       mode_t perms = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
       int opts
-       = (output_flags | O_NOCTTY
+       = (output_flags
           | (conversions_mask & C_NOCREAT ? 0 : O_CREAT)
           | (conversions_mask & C_EXCL ? O_EXCL : 0)
           | (seek_records || (conversions_mask & C_NOTRUNC) ? 0 : O_TRUNC));