update name of code to labcodes

labcodes/lab8/user/libs/umain.c

@@ -0,0 +1,34 @@
+#include <ulib.h>
+#include <unistd.h>
+#include <file.h>
+#include <stat.h>
+
+int main(int argc, char *argv[]);
+
+static int
+initfd(int fd2, const char *path, uint32_t open_flags) {
+    int fd1, ret;
+    if ((fd1 = open(path, open_flags)) < 0) {
+        return fd1;
+    }
+    if (fd1 != fd2) {
+        close(fd2);
+        ret = dup2(fd1, fd2);
+        close(fd1);
+    }
+    return ret;
+}
+
+void
+umain(int argc, char *argv[]) {
+    int fd;
+    if ((fd = initfd(0, "stdin:", O_RDONLY)) < 0) {
+        warn("open <stdin> failed: %e.\n", fd);
+    }
+    if ((fd = initfd(1, "stdout:", O_WRONLY)) < 0) {
+        warn("open <stdout> failed: %e.\n", fd);
+    }
+    int ret = main(argc, argv);
+    exit(ret);
+}
+