diff options
Diffstat (limited to 'm4/nullsort.m4')
| -rw-r--r-- | m4/nullsort.m4 | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/m4/nullsort.m4 b/m4/nullsort.m4 new file mode 100644 index 0000000..8173448 --- /dev/null +++ b/m4/nullsort.m4 @@ -0,0 +1,34 @@ +AC_DEFUN([jy_SORTZ], + [AC_PATH_PROG([SORT], [sort], [sort]) + AC_MSG_CHECKING([if $SORT supports the -z option]) +# find out if the sort command has a working -z option. +if $SORT -z -c < "${srcdir:-.}/m4/order-good.bin" 2>/dev/null >/dev/null +then + # sort has a -z option, but we have not yet established that + # sort thinks there is more than one input line there. We have + # to make sort -c do its thing with the input lines in the wrong + # order to determine that (we can't do it in one shot because + # if sort returns nonzero we cant tell that it wasn't just + # complaining about this unknown -z option. + if $SORT -z -c < "${srcdir:-.}/m4/order-bad.bin" 2>/dev/null >/dev/null + then + # sort likes -z but it doesn't seem to make \0 + # a delimiter. + ac_sort_has_z=false + else + ac_sort_has_z=true + fi +else + # Doesn't like the z option. + ac_sort_has_z=false +fi +if $ac_sort_has_z +then + AC_MSG_RESULT([yes]) + AC_SUBST(SORT_SUPPORTS_Z,[true]) +else + AC_MSG_RESULT([no]) + AC_SUBST(SORT_SUPPORTS_Z,[false]) +fi +]) + |