From: Jim Meyering <jim@meyering.net>
Date: Fri, 14 May 2004 07:34:09 +0000 (+0000)
Subject: Improve performance of `sort -m' on large files, at the cost of
X-Git-Tag: v5.3.0~1558
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8e0b4648a613daa8a4f01a058a2a7ffb982eafcd;p=thirdparty%2Fcoreutils.git

Improve performance of `sort -m' on large files, at the cost of
making some contrived examples unsafe.  POSIX allows this
optimization.  Performance problem reported by Jonathan Baker in
<http://mail.gnu.org/archive/html/bug-coreutils/2004-05/msg00071.html>.

(first_same_file): Do not treat input pipes
differently from other files.
---

diff --git a/src/sort.c b/src/sort.c
index a259ae9746..6fcfc69d7d 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -1878,9 +1878,7 @@ sortlines_temp (struct line *lines, size_t nlines, struct line *temp)
 }
 
 /* Return the index of the first of NFILES FILES that is the same file
-   as OUTFILE.  If none can be the same, return NFILES.  Consider an
-   input pipe to be the same as OUTFILE, since the pipe might be the
-   output of a command like "cat OUTFILE".  */
+   as OUTFILE.  If none can be the same, return NFILES.  */
 
 static int
 first_same_file (char * const *files, int nfiles, char const *outfile)
@@ -1910,7 +1908,7 @@ first_same_file (char * const *files, int nfiles, char const *outfile)
 	    ? fstat (STDIN_FILENO, &instat)
 	    : stat (files[i], &instat))
 	   == 0)
-	  && (S_ISFIFO (instat.st_mode) || SAME_INODE (instat, outstat)))
+	  && SAME_INODE (instat, outstat))
 	return i;
     }