Pintos: pintos/src/tests/userprog/read-zero.c Source File

00001 /* Try a 0-byte read, which should return 0 without reading
00002    anything. */
00003 
00004 #include <syscall.h>
00005 #include "tests/lib.h"
00006 #include "tests/main.h"
00007 
00008 void
00009 test_main (void) 
00010 {
00011   int handle, byte_cnt;
00012   char buf;
00013 
00014   CHECK ((handle = open ("sample.txt")) > 1, "open \"sample.txt\"");
00015 
00016   buf = 123;
00017   byte_cnt = read (handle, &buf, 0);
00018   if (byte_cnt != 0)
00019     fail ("read() returned %d instead of 0", byte_cnt);
00020   else if (buf != 123)
00021     fail ("0-byte read() modified buffer");
00022 }