minimal plan9port to cross-build Jehanne

lib/lib9/opentemp.c

@@ -0,0 +1,19 @@
+#include <u.h>
+#include <libc.h>
+
+int
+opentemp(char *template, int mode)
+{
+	int fd, fd1;
+
+	fd = mkstemp(template);
+	if(fd < 0)
+		return -1;
+	if((fd1 = open(template, mode)) < 0){
+		remove(template);
+		close(fd);
+		return -1;
+	}
+	close(fd);
+	return fd1;
+}