Non-portable mktemp usage
The mkvtoolnix configure script (due to ac/qt5.m4) is using
mktemp in a non-portable manner so it fails on OS X 10.10.x and older:
checking for Qt 6... no: disabled by user request checking for qmake... using supplied /opt/local/libexec/qt5/bin/qmake usage: mktemp [-d] [-q] [-t prefix] [-u] template ... mktemp [-d] [-q] [-u] -t prefix ./configure: line 9983: : No such file or directory grep: : No such file or directory checking for qmake's version... too old: configure: error: The Qt library is required for building MKVToolNix.
To be portable, you'll want something like
There is a second occurrence of
mktemp later in the file that will need similar treatment.