On 5/4/11 2:50 PM, Diego Biurrun wrote:
On Wed, May 04, 2011 at 12:04:09PM +0100, Måns Rullgård wrote:
Diego Biurrun<[email protected]> writes:
On Wed, May 04, 2011 at 11:23:16AM +0100, Måns Rullgård wrote:
Diego Biurrun<[email protected]> writes:
On Wed, May 04, 2011 at 10:23:17AM +0100, Måns Rullgård wrote:
Diego Biurrun<[email protected]> writes:
On some (BSD) systems _POSIX_C_SOURCE masks function definitions in
system header files. Avoid the #define in that case.
This allows eliminating some BSD-specific hacks.
--- a/configure
+++ b/configure
@@ -2310,7 +2310,9 @@ if test "$?" != 0; then
-add_cppflags -D_ISOC99_SOURCE -D_POSIX_C_SOURCE=200112
+add_cppflags -D_ISOC99_SOURCE
+check_func_headers unistd.h swab -D_POSIX_C_SOURCE=200112&&
+ add_cppflags -D_POSIX_C_SOURCE=200112
We need to be more careful here since this will omit the define on any
system lacking that function entirely. This could be any non-POSIX
system or a POSIX system without the X/Open extensions. Defining
_POSIX_C_SOURCE for non-POSIX systems is of course a bit odd.
What about running a two-staged test then: Pick some function to test
for and see if it is available without but not available with the
POSIX flag set. If both of these conditions trigger, skip adding
the POSIX flag to our CPPFLAGS.
That's what I was thinking. Perhaps something slightly less obscure
than swab() could be chosen though. Pick something with an XSI label
from http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
gethostid, lockf, nice, or sync might be good choices.
None of these are actually used in Libav either. I don't see any
better choice right now though. Do you have a suggestion which
one of those four is the most common and thus least likely to
be missing on some strange system?
Do a google code search: http://www.google.com/codesearch
This is practically useless since it does not allow regular expressions.
I get matches for unix_lockf, lockfile_foo and lockfile_bar and about
a trillion hits for stuff with sync in the name.
[^:alpha:]sync*[^:alpha:]\( lang:c
seems working fine (even if I'm not sure I used the most correct syntax)
lu
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