2 files changed, 29 insertions, 4 deletions

diff --git a/src/simple.c b/src/simple.c
index da79562..be92977 100644
--- a/src/simple.c
+++ b/src/simple.c
@@ -12,7 +12,7 @@
 static void
 usage(void)
 {
-        (void) fprintf(stderr, "compress [-d] infile outfile\n");
+        (void) fprintf(stderr, "simple [-d] infile outfile\n");
 }
 
 static void
@@ -142,10 +142,19 @@ main(int argc, char *argv[])
 
         if ( argc != 2 ) {
                 usage();
+                return EXIT_FAILURE;
+        }
+
+        FILE *in_file = fopen(argv[0], "rb");
+        if ( in_file == NULL ) {
+                error("fopen() on in_file failed");
         }
 
-        FILE *in_file  = fopen(argv[0], "rb");
         FILE *out_file = fopen(argv[1], "wb");
+        if ( out_file == NULL ) {
+                (void) fclose(in_file);
+                error("fopen() on out_file failed");
+        }
 
         if ( !decompress ) {
                 do_compress(in_file, out_file, compress_level);
diff --git a/src/stream.c b/src/stream.c
index 286f41a..c6d2d35 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -15,7 +15,14 @@ enum { BUFFER_SIZE = 8192 };
 static void
 usage(void)
 {
-        (void) fprintf(stderr, "compress [-d] infile outfile\n");
+        (void) fprintf(stderr, "stream [-d] infile outfile\n");
+}
+
+static void
+error(const char *msg)
+{
+        perror(msg);
+        exit(EXIT_FAILURE);
 }
 
 static void
@@ -162,10 +169,19 @@ main(int argc, char *argv[])
 
         if ( argc != 2 ) {
                 usage();
+                return EXIT_FAILURE;
+        }
+
+        FILE *in_file = fopen(argv[0], "rb");
+        if ( in_file == NULL ) {
+                error("fopen() on in_file failed");
         }
 
-        FILE *in_file  = fopen(argv[0], "rb");
         FILE *out_file = fopen(argv[1], "wb");
+        if ( out_file == NULL ) {
+                (void) fclose(in_file);
+                error("fopen() on out_file failed");
+        }
 
         if ( !decompress ) {
                 int error = do_compress(in_file, out_file, compress_level);