From: Richard W.M. Jones <rjones@redhat.com>
Date: Tue, 22 Oct 2013 10:59:30 +0000 (+0100)
Subject: Use posix_fadvise to tell the kernel how we use the output file.
X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=8365e963b4d7a085b7afc25d72ecf93fccb5f5fc;p=pxzcat.git

Use posix_fadvise to tell the kernel how we use the output file.
---

diff --git a/pxzcat.c b/pxzcat.c
index 346e3f8..a6becce 100644
--- a/pxzcat.c
+++ b/pxzcat.c
@@ -171,6 +171,9 @@ xzfile_uncompress (const char *filename, const char *outputfile,
   if (ftruncate (ofd, size) == -1)
     error (EXIT_FAILURE, errno, "ftruncate: %s", outputfile);
 
+  /* Tell the kernel we won't read the output file. */
+  posix_fadvise (fd, 0, 0, POSIX_FADV_RANDOM|POSIX_FADV_DONTNEED);
+
   /* Iterate over blocks. */
   iter_blocks (idx, nr_threads, filename, fd, outputfile, ofd);