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Re: git-svn failure when symlink added in svn

From
Junio C Hamano <junkio@cox.net>
Date
Apr 28, 2007, 17:31 UTC
Message-ID
<7virbgjthr.fsf@assigned-by-dhcp.cox.net>
In-Reply-To
<loom.20070428T144858-521@post.gmane.org>
Is it really the redirection that is the problem?

The process seeks $fh back to the beginning, reads 5 bytes from it (to ensure that is 'link '), and then forks to feed $fh to git-hash-object.

Now what do you really want to hash here? I do not know what this "file that begins with 'link '" magic is about, but I suspect that the child may or may not start reading from byte offset 5 of that file, depending on how the low-level I/O is tied to Perl.

Here is a little test script to imitate what the part in close_file sub is doing. What does it output on MacOS (or whatever systems that are having the same problem)?

On a Linux box, it appears that it reads the remainder of the file and the test script says "child says: >>12345", so I am assuming that is what close_file sub wants to do. If my suspicion is correct, you would get "child says: >>link 12345", in which case sysseek() commented out below would help, perhaps.

-- >8 -- #!/usr/bin/perl -w

open F, ">footest"; print F "link 12345\n"; close F;

my ($fh, $buf, $n, $pid, $out);

open $fh, "<footest"; seek($fh, 0, 0); $n = read($fh, $buf, 5); print "read[$n]: $buf\n";

$pid = open $out , '-|';
if (!$pid) {
	my $at = tell $fh;
	print "child: at $at\n";
	# We may want to do
        #
	#	 sysseek($fh, 5, 0);
        #
        # here.
	open STDIN, '<&', $fh;
	exec qw(sed -e s/^/>>/);
}
while (my $read = <$out>) {
	print "child says: $read";
}
close ($out);
close ($fh);
Previous: Seth FalconNext: Seth Falcon
Message 8 of 24 in “git-svn failure when symlink added in svn”
  1. Seth FalconApr 14, 2007
  2. Eric WongApr 14, 2007
  3. Seth FalconApr 16, 2007
  4. Alexander KlinkApr 26, 2007
  5. Linus TorvaldsApr 27, 2007
  6. Alexander KlinkApr 28, 2007
  7. Seth FalconApr 28, 2007
  8. Junio C HamanoApr 28, 2007
  9. Seth FalconApr 28, 2007
  10. Junio C HamanoApr 28, 2007
  11. Seth FalconApr 28, 2007
  12. Junio C HamanoApr 28, 2007
  13. Eric WongApr 29, 2007
  14. Junio C HamanoApr 29, 2007
  15. Eric WongApr 29, 2007
  16. Alexander KlinkApr 30, 2007
  17. Junio C HamanoApr 30, 2007
  18. Eric WongApr 30, 2007
  19. Seth FalconApr 30, 2007
  20. Alexander KlinkMay 1, 2007
  21. Eric WongApr 29, 2007
  22. Seth FalconApr 30, 2007
  23. Eric WongApr 30, 2007
  24. Seth FalconMay 1, 2007

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