diff --git a/findutils/grep.c b/findutils/grep.c
index 6af1b46..fc78938 100644
--- a/findutils/grep.c
+++ b/findutils/grep.c
@@ -126,7 +126,7 @@
 typedef struct grep_list_data_t {
 	char *pattern;
 	regex_t preg;
-#define PATTERN_MEM_A 1
+#define ALLOCATED 1
 #define COMPILED 2
 	int flg_mem_alocated_compiled;
 } grep_list_data_t;
@@ -363,10 +363,10 @@
 
 		fopt = cur->link;
 		free(cur);
-		f = xfopen(ffile, "r");
+		f = xfopen_stdin(ffile);
 		while ((line = xmalloc_fgetline(f)) != NULL) {
 			llist_add_to(&pattern_head,
-				new_grep_list_data(line, PATTERN_MEM_A));
+				new_grep_list_data(line, ALLOCATED));
 		}
 	}
 }
@@ -486,7 +486,7 @@
 		argc--;
 	}
 
-	/* argv[(optind)..(argc-1)] should be names of file to grep through. If
+	/* argv[0..(argc-1)] should be names of file to grep through. If
 	 * there is more than one file to grep, we will print the filenames. */
 	if (argc > 1)
 		print_filename = 1;
@@ -535,9 +535,9 @@
 			grep_list_data_t *gl = (grep_list_data_t *)pattern_head_ptr->data;
 
 			pattern_head = pattern_head->link;
-			if ((gl->flg_mem_alocated_compiled & PATTERN_MEM_A))
+			if (gl->flg_mem_alocated_compiled & ALLOCATED)
 				free(gl->pattern);
-			if ((gl->flg_mem_alocated_compiled & COMPILED))
+			if (gl->flg_mem_alocated_compiled & COMPILED)
 				regfree(&(gl->preg));
 			free(gl);
 			free(pattern_head_ptr);