>>>>> "Jim" == Jim Meyering <[EMAIL PROTECTED]> writes:
Jim> I vaguely recall that we couldn't depend on touch. However, it
Jim> *is* in the list of programs mentioned in standards.info's
Jim> `Utilities in Makefiles' section.
Anyway, we really need to know how to create portably empty files, we
use it at other places IIRC.
Jim> | or
Jim> |
Jim> | cp /dev/null empty
Jim> Not everyone has a /dev/null.
Huh??? What for instance?
But anyway, /dev/null is *widespread* in Autoconf, so we shouldn't
bother.
Here is my proposal:
Index: tests/atgeneral.m4
===================================================================
RCS file: /cvs/autoconf/tests/atgeneral.m4,v
retrieving revision 1.61
diff -u -u -r1.61 atgeneral.m4
--- tests/atgeneral.m4 2001/03/13 12:43:15 1.61
+++ tests/atgeneral.m4 2001/03/19 10:11:00
@@ -187,9 +187,16 @@
# Tests to run.
test -z "$at_tests" && at_tests=$at_tests_all
+# Can we diff with `/dev/null'? DU 5.0 refuses.
+if diff /dev/null /dev/null >/dev/null 2>&1; then
+ at_devnull='/dev/null'
+else
+ cp /dev/null at-devnull
+ at_devnull='at-devnull'
+fi
+
# Use `diff -u' when possible.
-: >empty
-if diff -u empty empty >/dev/null 2>&1; then
+if diff $at_devnull $at_devnull >/dev/null 2>&1; then
at_diff='diff -u'
else
at_diff='diff'
@@ -531,14 +538,14 @@
stderr, [(echo stderr:; tee stderr <at-stderr) >&5],
ignore, [(echo stderr:; cat at-stderr) >&5],
experr, [$at_diff experr at-stderr >&5 || at_failed=:],
- [], [$at_diff empty at-stderr >&5 || at_failed=:],
+ [], [$at_diff $at_devnull at-stderr >&5 || at_failed=:],
[echo $at_n "AS_ESCAPE([$4])$at_c" | $at_diff - at-stderr >&5 || at_failed=:])
dnl Check stdout.
m4_case([$3],
stdout, [(echo stdout:; tee stdout <at-stdout) >&5],
ignore, [(echo stdout:; cat at-stdout) >&5],
expout, [$at_diff expout at-stdout >&5 || at_failed=:],
- [], [$at_diff empty at-stdout >&5 || at_failed=:],
+ [], [$at_diff $at_devnull at-stdout >&5 || at_failed=:],
[echo $at_n "AS_ESCAPE([$3])$at_c" | $at_diff - at-stdout >&5 || at_failed=:])
dnl Check exit val. Don't `skip' if we are precisely checking $? = 77.
case $at_status in
