How to create a unique file path in a shell cross-platform? I have looked around on most of the answers and it seems that no cross-platform/portable solution is simple enough. mktemp seems to be the most solid alternative on platforms where mktemp is availible. When it is not availible /dev/random on this stackoverflow question can also be an alternative. If some kind of time traceability is wanted then what would be the next alternative?
The most simple that is included in the posix standard is to use mktemp. If that is not availible date is the next second option. %s parameter of date may also not be availible on all legacy platforms.
date "+%s-%N"
%s seconds since epoch and %N nano seconds to be dead sure of the uniqueness.
With more context:
TEMPDIR=/tmp/`date "+%s-%N"`