the kernel-specific functions can fetch and use additional data it may need

Signed-off-by: Mattias Andrée <maandree@member.fsf.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/png.h b/src/png.h
index b621234..0f5d93f 100644
--- a/src/png.h
+++ b/src/png.h
@@ -58,8 +58,10 @@
  * @param   width   The width of the image.
  * @param   height  The height of the image.
  * @param   imgfd   The file descriptor connected to conversion process's stdin.
+ * @param   data    Additional data for `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
 int
-save_png (int fbfd, long width, long height, int imgfd);
+save_png (int fbfd, long width, long height, int imgfd, void *restrict data);