2 files changed, 17 insertions, 2 deletions
diff --git a/src/lib/file.c b/src/lib/file.c
index e2c7c5d..494e740 100644
--- a/src/lib/file.c
+++ b/src/lib/file.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include "file.h"
 #include "util.h"
@@ -9,9 +10,9 @@ struct filedata readfile(FILE *fp) {
 
   f.lc = 0;
   f.len = 0;
+  f.binary = 0;
 
   size_t bufsize = 4;
-
   f.buf = malloc(bufsize);
   if (f.buf == NULL)
     die("malloc");
@@ -37,5 +38,19 @@ struct filedata readfile(FILE *fp) {
     f.buf[f.len++] = c;
   }
 
+  // guess if printable
+  // from https://github.com/sharkdp/content_inspector/blob/master/src/lib.rs
+  int testlen = 64;
+  char *testbuf[testlen];
+  memcpy(testbuf, f.buf, testlen);
+
+  char *result = memchr(testbuf, 0x00, testlen);
+
+  if (result) {
+    f.binary = 1;
+  } else {
+    f.binary = 0;
+  }
+
   return f;
 }
diff --git a/src/lib/util.c b/src/lib/util.c
index 6561af8..d2d4f6a 100644
--- a/src/lib/util.c
+++ b/src/lib/util.c
@@ -7,7 +7,7 @@ void die(const char *message) {
   exit(1);
 }
 
-char *formatBytes(size_t bytes, float *rounded) {
+char *formatbytes(size_t bytes, float *rounded) {
   char *SIZES[] = {"bytes", "kB", "MB", "GB"};
 
   size_t size = bytes;