+ test -f "$fsha1path" -a ! "$fsha1path" -nt "$packfile" -a \
+ ! "$fsha1path" -ot "$packfile" &&
+ test -f "$csha1path" -a ! "$csha1path" -nt "$packfile" -a \
+ ! "$csha1path" -ot "$packfile" &&
+ test -f "$tsha1path" -a ! "$tsha1path" -nt "$packfile" -a \
+ ! "$tsha1path" -ot "$packfile"
+'
"Test" primaries -nt/-ot are unfortunately excluded from POSIX.
hrmph, and it even worked on solaris ksh.
FYI, also works with dash, and there is a use of '-nt' in git-mergetool.sh
which is not exercised by the test suite.
Maybe I'll think about a perl version.
Also, do you have a url to your posix reference?
-brandon