1 files changed, 1 insertions, 0 deletions

diff --git a/bin/pngo.c b/bin/pngo.c
index ef4ded36..84c81444 100644
--- a/bin/pngo.c
+++ b/bin/pngo.c
@@ -23,6 +23,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sysexits.h>
+#include <unistd.h>
 #include <zlib.h>
 
 #define PACKED __attribute__((packed))