LIBPNGPF(3) Library Functions Manual LIBPNGPF(3)

# [NAME](#NAME)

libpng - Portable Network Graphics (PNG) Reference Library 1.6.59

# [SYNOPSIS](#SYNOPSIS)

**#include "pngpriv.h"**

# [DESCRIPTION](#DESCRIPTION)

As of libpng version 1.5.1, this manual is no longer maintained. The private function prototypes, declared in private header files, should not be accessed by applications.

# [SEE ALSO](#SEE_ALSO)

[**libpng**(3)](/man/os/libpng/libpng.3)

# [AUTHORS](#AUTHORS)

Cosmin Truta, Glenn Randers-Pehrson

September 28, 2026

---

Document: libpngpf(3) from libpng 1.6.59-r1 (Chainguard OS)
Source: https://github.com/pnggroup/libpng