$OpenBSD: patch-src_ptclib_pwavfile_cxx,v 1.1 2018/12/20 20:18:53 naddy Exp $

Index: src/ptclib/pwavfile.cxx
--- src/ptclib/pwavfile.cxx.orig
+++ src/ptclib/pwavfile.cxx
@@ -61,6 +61,7 @@ inline PBoolean ReadAndCheck(PWAVFile & file, void * b
 
 #if PBYTE_ORDER==PBIG_ENDIAN
 #  if defined(USE_SYSTEM_SWAB)
+#    include <unistd.h>
 #    define SWAB(a,b,c) ::swab(a,b,c)
 #  else
 static void SWAB(const void * void_from, void * void_to, register size_t len)
