Check for mkstemp, added a port implementation if it is not
present. Use mkstemp() in various places needing tmp files.

diff --git a/configure b/configure
index b96b12e..eb19ffc 100755
--- a/configure
+++ b/configure
@@ -11199,6 +11199,7 @@
 
 
 
+
 for ac_func in \
 	__libc_fork \
 	_lwp_create \
@@ -11226,6 +11227,7 @@
 	lseek64 \
 	lstat \
 	memmove \
+	mkstemp \
 	mmap \
 	pclose \
 	popen \