libc: implement err/warn functions

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/libc/stdio/perror.c b/lib/libc/stdio/perror.c
index ad314038..02e14a42 100644
--- a/lib/libc/stdio/perror.c
+++ b/lib/libc/stdio/perror.c
@@ -8,19 +8,21 @@
 
 void perror(const char *s)
 {
+	char *errstr;
 	struct iovec iov[4];
 
-	char *errstr = strerror(errno);
-
 	if (s != NULL && *s != '\0') {
 		iov[0].iov_base = (void *)s;
 		iov[0].iov_len = strlen(s);
+
 		iov[1].iov_base = ": ";
 		iov[1].iov_len = 2;
 	}
 
+	errstr = strerror(errno);
 	iov[s != NULL && *s != '\0' ? 2 : 0].iov_base = errstr;
 	iov[s != NULL && *s != '\0' ? 2 : 0].iov_len = strlen(errstr);
+
 	iov[s != NULL && *s != '\0' ? 3 : 1].iov_base = "\n";
 	iov[s != NULL && *s != '\0' ? 3 : 1].iov_len = 1;