Hi, I am having the same problem with the original poster.
I'm using GNU tar 1.28 and gzip 1.6 from MacPorts. The failure happens in both creation and extraction of combined tar & gzip: $ sw_vers ProductName: Mac OS X ProductVersion: 10.10.5 BuildVersion: 14F27 bash-3.2$ which tar gzip /opt/local/libexec/gnubin/tar /opt/local/bin/gzip $ tar -czf tarball.tgz folder # failed silently (instantly returns) $ tar -cf tarball.tar folder # succeed $ gzip tarball.tar # succeed $ tar -xzf tarball.tar.gz # failed with tar: Child died with signal 11 $ unzip tarball.tar.gz # succeed $ tar -xf tarball.tar # succeed How does tar finds the gzip/gunzip/zcat binary to be used? I only manipulate PATH to use GNU binaries without changing the links in /usr/bin/ meaning that the links in /usr/bin/ still refer to Apple/BSD version Please add me in the TO/CC since I'm not in the mailing list. Thanks, Arief