fix race in holding() check in acquire()

give cpu1 a TSS and gdt for when it enters scheduler()
and a pseudo proc[] entry for each cpu
cpu0 waits for each other cpu to start up
read() for files

1 files changed, 35 insertions, 0 deletions

diff --git a/cat.c b/cat.c
new file mode 100644
index 0000000..8154ae2
--- /dev/null
+++ b/cat.c
@@ -0,0 +1,35 @@
+#include "user.h"
+
+char buf[513];
+
+int
+main(int argc, char *argv[])
+{
+  int fd, i, cc;
+
+  if(argc < 2){
+    puts("Usage: cat files...\n");
+    exit();
+  }
+
+  for(i = 1; i < argc; i++){
+    fd = open(argv[i], 0);
+    if(fd < 0){
+      puts("cat: cannot open ");
+      puts(argv[i]);
+      puts("\n");
+      exit();
+    }
+    while((cc = read(fd, buf, sizeof(buf) - 1)) > 0){
+      buf[cc] = '\0';
+      puts(buf);
+    }
+    if(cc < 0){
+      puts("cat: read error\n");
+      exit();
+    }
+    close(fd);
+  }
+
+  exit();
+}