From: Jim Meyering <jim@meyering.net>
Date: Sat, 25 Nov 2000 07:20:51 +0000 (+0000)
Subject: (S_TYPEISSHM): New macro.
X-Git-Tag: FILEUTILS-4_0_33~39
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7d57b3419605e20c8b206c1f5902e54a2611ac75;p=thirdparty%2Fcoreutils.git

(S_TYPEISSHM): New macro.
(main): Report failed fstat.
Complain only when ftruncate fails on a regular file,
a directory, or a shared memory object.
---

diff --git a/src/dd.c b/src/dd.c
index 259bfa2de5..01447e50a2 100644
--- a/src/dd.c
+++ b/src/dd.c
@@ -48,6 +48,10 @@
 # define SIGINFO SIGUSR1
 #endif
 
+#ifndef S_TYPEISSHM
+# define S_TYPEISSHM(Mode) 0
+#endif
+
 #define ROUND_UP_OFFSET(X, M) ((M) - 1 - (((X) + (M) - 1) % (M)))
 #define PTR_ALIGN(Ptr, M) ((Ptr) \
 			   + ROUND_UP_OFFSET ((char *)(Ptr) - (char *)0, (M)))
@@ -1260,11 +1264,18 @@ main (int argc, char **argv)
 	      o = seek_bytes;
 	    }
 
-	  /* Attempt to use ftruncate only if STDOUT refers to a regular file.
-	     On Linux 2.4.0, ftruncate fails with for non-regular files.  */
-	  if (fstat (STDOUT_FILENO, &stdout_stat) == 0
-	      && S_ISREG (stdout_stat.st_mode)
-	      && ftruncate (STDOUT_FILENO, o) < 0)
+	  if (fstat (STDOUT_FILENO, &stdout_stat) != 0)
+	    error (1, errno, _("cannot fstat %s"), quote (output_file));
+
+	  /* Complain only when ftruncate fails on a regular file, a
+	     directory, or a shared memory object, as the 2000-08
+	     POSIX draft specifies ftruncate's behavior only for these
+	     file types.  For example, do not complain when Linux 2.4
+	     ftruncate fails on /dev/fd0.  */
+	  if (ftruncate (STDOUT_FILENO, o) != 0
+	      && (S_ISREG (stdout_stat.st_mode)
+		  || S_ISDIR (stdout_stat.st_mode)
+		  || S_TYPEISSHM (stdout_stat.st_mode)))
 	    {
 	      char buf[LONGEST_HUMAN_READABLE + 1];
 	      if (seek_record)