[hackers] [dwm] config.mk: update to _XOPEN_SOURCE=700L || NRK

[git]

commit 348f6559ab0d4793db196ffa56ba96ab95a594a6
Author:     NRK <n...@disroot.org>
AuthorDate: Fri Feb 17 11:05:09 2023 +0600
Commit:     Hiltjo Posthuma <hil...@codemadness.org>
CommitDate: Fri Feb 17 15:27:34 2023 +0100

    config.mk: update to _XOPEN_SOURCE=700L
    
    SA_NOCLDWAIT is marked as XSI in the posix spec [0] and FreeBSD and NetBSD
    seems to more be strict about the feature test macro [1].
    
    so update the macro to use _XOPEN_SOURCE=700L instead, which is equivalent 
to
    _POSIX_C_SOURCE=200809L except that it also unlocks the X/Open System
    Interfaces.
    
    [0]: 
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/signal.h.html#tag_13_42
    [1]: https://lists.suckless.org/dev/2302/35111.html
    
    Tested on:
    * NetBSD 9.3 (fixed).
    * FreeBSD 13 (fixed).
    * Void Linux musl.
    * Void Linux glibc.
    * OpenBSD 7.2 (stable).
    * Slackware 11.
    
    Reported-by: beastie <pufferf...@riseup.net>

diff --git a/config.mk b/config.mk
index ef8acf7..ba64d3d 100644
--- a/config.mk
+++ b/config.mk
@@ -26,7 +26,7 @@ INCS = -I${X11INC} -I${FREETYPEINC}
 LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS}
 
 # flags
-CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_POSIX_C_SOURCE=200809L 
-DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}
+CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700L 
-DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}
 #CFLAGS   = -g -std=c99 -pedantic -Wall -O0 ${INCS} ${CPPFLAGS}
 CFLAGS   = -std=c99 -pedantic -Wall -Wno-deprecated-declarations -Os ${INCS} 
${CPPFLAGS}
 LDFLAGS  = ${LIBS}