diff --git a/writeimg.c b/writeimg.c
index 538f480..e48c1c3 100644
--- a/writeimg.c
+++ b/writeimg.c
@@ -194,6 +194,11 @@ int main(int argc, char *argv[]) {
         exit(EXIT_FAILURE);
     }
 
+    if (0 != strncmp(wjob.dev_name, "/dev/", 4)) {
+        printf("\"%s\" does not appear to be a block device...\n", wjob.dev_name);
+        exit(EXIT_FAILURE);
+    }
+
     printf("Writing %s to %s\n", wjob.filename, wjob.dev_name);
 
     wjob.buffer = malloc(BLOCKSIZE);