Experimental support for GNU Pth's Posix Thread API. This might be a

suitable for systems with poor (or nonexistant) Pthread implementations.

build/openldap.m4

@@ -605,6 +605,27 @@ fi
 ])
 dnl
 dnl ====================================================================
+dnl Check GNU Pth pthread Header
+dnl
+dnl defines ol_cv_header linux_threads to 'yes' or 'no'
+dnl		'no' implies pthreads.h is not LinuxThreads or pthreads.h
+dnl		doesn't exists.  Existance of pthread.h should separately
+dnl		checked.
+dnl 
+AC_DEFUN([OL_HEADER_GNU_PTH_PTHREAD_H], [
+	AC_CACHE_CHECK([for GNU Pth pthread.h],
+		[ol_cv_header_gnu_pth_pthread_h],
+		[AC_EGREP_CPP(__gnu_pth__,
+			[#include <pthread.h>
+#ifdef _POSIX_THREAD_IS_GNU_PTH
+	__gnu_pth__
+#endif
+],
+			[ol_cv_header_gnu_pth_pthread_h=yes],
+			[ol_cv_header_gnu_pth_pthread_h=no])
+		])
+])dnl
+dnl ====================================================================
 dnl Check LinuxThreads Header
 dnl
 dnl defines ol_cv_header linux_threads to 'yes' or 'no'

configure.in

@@ -896,7 +896,7 @@ ol_link_threads=no
 if test $ol_with_threads = auto -o $ol_with_threads = yes \
 	-o $ol_with_threads = posix ; then
 
-	AC_CHECK_HEADERS(pthread.h sched.h)
+	AC_CHECK_HEADERS(pthread.h)
 
 	if test $ac_cv_header_pthread_h = yes ; then
 		OL_POSIX_THREAD_VERSION
@@ -915,6 +915,11 @@ if test $ol_with_threads = auto -o $ol_with_threads = yes \
 		ol_with_threads=found
 
 		OL_HEADER_LINUX_THREADS
+		OL_HEADER_GNU_PTH_PTHREAD_H
+
+		if test $ol_cv_header_gnu_pth_pthread_h = no ; then
+			AC_CHECK_HEADERS(sched.h)
+		fi
 
 		dnl Now the hard part, how to link?
 		dnl

libraries/libldap_r/thr_posix.c

@@ -126,13 +126,20 @@ ldap_pvt_thread_kill( ldap_pvt_thread_t thread, int signo )
 int 
 ldap_pvt_thread_yield( void )
 {
-#ifdef HAVE_SCHED_YIELD
+#ifdef _POSIX_THREAD_IS_GNU_PTH
+	sched_yield();
+	return 0;
+
+#elif HAVE_SCHED_YIELD
 	return sched_yield();
+
 #elif HAVE_PTHREAD_YIELD
 	pthread_yield();
 	return 0;
+
 #elif HAVE_THR_YIELD
 	return thr_yield();
+
 #else
 	return 0;
 #endif