X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Funistd%2Fdup2.c;h=8f43c6ddfe8983e9565d6a14a10f423c9fd55f05;hb=3934f49c01d35565a9b74b3f9b29a913efa7c973;hp=7945f853cae600b317ebab09306c4a8df1d06aa4;hpb=aa398f56fa398f2202b04e82c67f822f3233786f;p=musl

diff --git a/src/unistd/dup2.c b/src/unistd/dup2.c
index 7945f853..8f43c6dd 100644
--- a/src/unistd/dup2.c
+++ b/src/unistd/dup2.c
@@ -1,7 +1,20 @@
 #include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
 #include "syscall.h"
 
 int dup2(int old, int new)
 {
-	return syscall(SYS_dup2, old, new);
+	int r;
+#ifdef SYS_dup2
+	while ((r=__syscall(SYS_dup2, old, new))==-EBUSY);
+#else
+	if (old==new) {
+		r = __syscall(SYS_fcntl, old, F_GETFD);
+		if (r >= 0) return old;
+	} else {
+		while ((r=__syscall(SYS_dup3, old, new, 0))==-EBUSY);
+	}
+#endif
+	return __syscall_ret(r);
 }