On 2015-04-20, Murthy Gandikota wrote: > >> Then it looks like you have a DOUBLE-compressed file. That is, someone > >> took a .tar.gz file, and ran THAT through gzip again (which seldom does > >> anything except make a LARGER file - because the first round of > >> compression removed any redundancy). Tar cannot read a > >> double-compressed stream, but breaking things into two steps lets you > >> get back to a single compressed stream, where the tar call then > >> auto-decompresses because you weren't supplying an explicit 'z' the > >> second time around. To prove it, try: > >> > >> gunzip <mytar.gz>mytar > >> tar zxvf mytar > >> > >> and if it still untars with an explicit decompression, then you have > >> proven that your original file was double-compressed. Also, if I'm > >> right about double compression, then mytar.gz would likely be slightly > >> larger than mytar (rather than the usual case of the .gz being > >> noticeably smaller). > >> > >> -- > >> Eric Blake eblake redhat com +1-919-301-3266 > >> Libvirt virtualization library http://libvirt.org > >> > > > > Yes, Sir. It did untar properly. So the problem is with the > > server compressing during the download (I get the file from a > > http server)? > > Thanks a lot for your help
> It would be doubly nice if cygwin handled it ;-) It seems gunzip > had no problem recognizing the file as double compressed. > Thanks all for the help. I think you misunderstand. Gunzip decompresses once. As Eric wrote, tar recognizes compressed files and will decompress them automatically even without specifying a compression flag such as 'z'. The second decompression is done by tar, not by gunzip. Regards, Gary -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
