1 files changed, 10 insertions, 21 deletions
diff --git a/userspace/piper.c b/userspace/piper.c
index f45248e..80cbd27 100644
--- a/userspace/piper.c
+++ b/userspace/piper.c
@@ -1,38 +1,27 @@
 #include <stdio.h>
 #include "newcalls.h"
 
+extern **environ;
+
 int main()
 {
     int fds[2];
     _pipe(fds);
 
-    printf("opened pipe / in fd=%d,out fd=%d\n",fds[0],fds[1]);
-
     int pid=_fork();
 
     if(pid)
     {
-	while(1) // read forever from our pipe and echo to stdout
-	{
-	    char buf[256];
-	    int len=fread(buf,1,255,fds[0]);
-	    //int len=_read(fds[0],buf,255);
-	    buf[len]=0;
-	    printf("-\n");
-	    printf("%s\n",buf);
-	    printf("-\n");
-	}
-
+	_close(fds[1]);
+	_dup2(fds[0],0); // replace stdin with the read-end of pipe
+	char *args[]={"grep",NULL};
+	_execve("/bin/grep",args,environ);
     }
     else
     {
-
-	// write to our pipe
-        _write(fds[1],"Hello\n",fds[1]);
-        _write(fds[1],"Bello\n",fds[1]);
-
-	// hang forever
-	while(1);
+	_close(fds[0]);
+	_dup2(fds[1],1); // replace stdout with the write-end of our pipe
+	char *args[]={"cat","hello.txt",0};
+	_execve("/bin/cat",args,environ);
     }
-
 }