Signed-off-by: Mans Rullgard <mans@mansr.com>

This is different from AVERROR(EINTR) because calls that fail with EINTR
should usually be restarted.

Signed-off-by: Nicolas George <nicolas.george@normalesup.org>
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

Originally committed as revision 26056 to svn://svn.ffmpeg.org/ffmpeg/trunk

not defined.

This allows applications to check if av_strerror() cannot provide a
meaningful representation for the provided error code, without having
to actually check the filled string.

Originally committed as revision 23031 to svn://svn.ffmpeg.org/ffmpeg/trunk

number if strerror_r() did not succeed for whatever reason.

This avoids the need for the application to fill the string in case
strerror_r() fails, for example because the error code is not known.

Originally committed as revision 23015 to svn://svn.ffmpeg.org/ffmpeg/trunk

instead which is semantically equivalent.

See the thread:
Subject: [FFmpeg-devel] [RFC] The meaning of AVERROR_NOTSUPP
Date: Sat, 27 Mar 2010 00:51:13 +0100

Originally committed as revision 22981 to svn://svn.ffmpeg.org/ffmpeg/trunk

Originally committed as revision 22684 to svn://svn.ffmpeg.org/ffmpeg/trunk