X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fsem_trywait.c;fp=src%2Fthread%2Fsem_trywait.c;h=d0e928ef67d2048f4bbf1f1214a30407d8dbe7c8;hb=6fc5fdbdc70dd17ea8e681a361fb4dae541ee953;hp=0000000000000000000000000000000000000000;hpb=03dcc3417ce4388a652bdd053cb2b6af860daf00;p=musl

diff --git a/src/thread/sem_trywait.c b/src/thread/sem_trywait.c
new file mode 100644
index 00000000..d0e928ef
--- /dev/null
+++ b/src/thread/sem_trywait.c
@@ -0,0 +1,11 @@
+#include <semaphore.h>
+#include "pthread_impl.h"
+
+int sem_trywait(sem_t *sem)
+{
+	int val = a_fetch_add(sem->__val, -1);
+	if (val > 0) return 0;
+	a_inc(sem->__val);
+	errno = EAGAIN;
+	return -1;
+}