Add ucat

.gitignore

@@ -1,3 +1,4 @@
 kernel-hdr
 build
 progs/rsh
+progs/rc

etc/inittab

@@ -0,0 +1,3 @@
+# Runlevels: 1
+
+l0:1:once:/bin/login

progs/base/bin/ucat.c

@@ -0,0 +1,38 @@
+#include <sys/socket.h>
+#include <string.h>
+#include <ygg/un.h>
+#include <unistd.h>
+#include <stdio.h>
+
+int main(int argc, char **argv) {
+    struct sockaddr_un un;
+    ssize_t rd;
+    int fd;
+    char buf[1024];
+
+    if (argc != 2) {
+        fprintf(stderr, "usage: %s SOCKET\n", argv[0]);
+        return -1;
+    }
+
+    un.sun_family = AF_UNIX;
+    strcpy(un.sun_path, argv[1]);
+
+    if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
+        perror("socket()");
+        return -1;
+    }
+
+    if (connect(fd, (struct sockaddr *) &un, sizeof(un)) != 0) {
+        perror("connect()");
+        return -1;
+    }
+
+    while ((rd = recv(fd, buf, sizeof(buf), 0)) > 0) {
+        write(STDOUT_FILENO, buf, rd);
+    }
+
+    close(fd);
+
+    return 0;
+}