Modify README. Remove redundant assignment from overwrite.c.

Add additional error handling to overwrite.c.

README

@@ -13,4 +13,5 @@
 	     line, so long as it doesn't cause a word-split.
     -overwrite: Reads stdin and writes it to the provided file. [done]
     -shuf: Accepts an arbitrary number of arguments; returns one at random.
+    -rand: Shell interface to the C rand() function. 
     

src/overwrite.c

@@ -14,7 +14,6 @@ int main(int argc, char **argv)
     char *buf;
     FILE *fp;
     strlen = 0;
-    buflen = 0;
     /* arbitrary */
     buflen = 4096;
 
@@ -29,9 +28,10 @@ int main(int argc, char **argv)
         
         for(;((c = getchar()) != EOF);)
             {
-	    if(strlen == buflen)
+            if(strlen == buflen && !(buf = realloc(buf, (buflen*=2))))
                 {
-		buf = realloc(buf, (buflen*=2));
+                /* realloc failed */
+		throw(MALLOC_FAIL, NULL);
 		}
             buf[strlen++] = c;
             }