2 files changed, 3 insertions, 2 deletions
diff --git a/fonts.c b/fonts.c
index f72f38c..b8299a3 100644
--- a/fonts.c
+++ b/fonts.c
@@ -2,7 +2,7 @@
 
 #include "fonts.h"
 
-void render(unsigned char *input, int input_len, unsigned char *output, int max_output_len, int skip_unprintables)
+int render(unsigned char *input, int input_len, unsigned char *output, int max_output_len, int skip_unprintables)
 {
   memset(output, 0, max_output_len);
   int output_i = 0;
@@ -24,4 +24,5 @@ void render(unsigned char *input, int input_len, unsigned char *output, int max_
       output[output_i*(SYMBOL_WIDTH+1) + i] = symbols[c*SYMBOL_WIDTH + i];
     output_i++;
   }
+  return output_i*(SYMBOL_WIDTH+1);
 }
diff --git a/fonts.h b/fonts.h
index 2ccd92a..c577d82 100644
--- a/fonts.h
+++ b/fonts.h
@@ -100,4 +100,4 @@ static char const symbols[96 * SYMBOL_WIDTH] = {
   0x00,0x02,0x05,0x02,0x00   // °
 };
 
-void render(unsigned char *input, int input_len, unsigned char *output, int max_output_len, int skip_unprintables);
+int render(unsigned char *input, int input_len, unsigned char *output, int max_output_len, int skip_unprintables);