Use -D_XOPEN_SOURCE=700 - ubase - suckless linux base utils
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       ---
   DIR commit 74c0abb6a2f9b8cac0653f1b96646aaf74b91a68
   DIR parent cee1a0170d17f6f9bbddcaa97a30dd7fa4f0387f
  HTML Author: sin <sin@2f30.org>
       Date:   Sun, 30 Nov 2014 14:12:40 +0000
       
       Use -D_XOPEN_SOURCE=700
       
       Diffstat:
         M config.mk                           |       2 +-
       
       1 file changed, 1 insertion(+), 1 deletion(-)
       ---
   DIR diff --git a/config.mk b/config.mk
       @@ -10,7 +10,7 @@ LD = $(CC)
        AR = ar
        RANLIB = ranlib
        
       -CPPFLAGS = -D_XOPEN_SOURCE -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64
       +CPPFLAGS = -D_FILE_OFFSET_BITS=64 -D_XOPEN_SOURCE=700 -D_GNU_SOURCE
        CFLAGS   = -std=c99 -Wall -Wextra
        LDLIBS   = -lcrypt
        LDFLAGS  = -s