Originally committed as revision 23910 to svn://svn.ffmpeg.org/ffmpeg/trunk
* error. Even in case of failure av_strerror() will print a generic
* error message indicating the errnum provided to errbuf.
*
+ * @param errnum error code to describe
+ * @param errbuf buffer to which description is written
* @param errbuf_size the size in bytes of errbuf
* @return 0 on success, a negative value if a description for errnum
* cannot be found