remove initfd for ucore programs

ucore/src/ulibs/umain.c

@@ -5,31 +5,8 @@
 
 int main(int argc, char *argv[]);
 
-static int
-initfd(int fd2, const char *path, uint32_t open_flags) {
-    int fd1;
-    if ((fd1 = open(path, open_flags)) < 0) {
-        return fd1;
-    }
-    int ret = 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);
 }
-