1 files changed, 1 insertions, 0 deletions
diff --git a/rubyio.h b/rubyio.h
index 3ec91680b5..8d2a307514 100644
--- a/rubyio.h
+++ b/rubyio.h
@@ -57,6 +57,7 @@ typedef struct OpenFile {
 FILE *rb_fopen _((const char*, const char*));
 FILE *rb_fdopen _((int, const char*));
 int rb_getc _((FILE*));
+long rb_io_fread _((char *, long, FILE *));
 int  rb_io_mode_flags _((const char*));
 void rb_io_check_writable _((OpenFile*));
 void rb_io_check_readable _((OpenFile*));