问题:

I want some library (API) to open, seek, read, write ... (in one word to process) gzip files. Is there any open-source cross-platform ones for C or C++?

回答1:

Yes. Zlib is the one.

There is also this related question on how to process gzip files more easily and conveniently in C++. The most notable and up to date suggestion seems to be the GZip filters in Boost.IOStreams, which I have good experience with myself.

回答2:

Yes, sure, zlib is the basic library and it has additional bindings other languages as listed on the webpage as eg gzstream providing a C++ wrapper to the gz* functions.

zlib, being a C-language library, is also extremely portable and cross-platform. See the webpage for links to Solaris, SCO, BeOS, MaxOS, OS/2 (!!), Palm Pilot, Newton (!!), Windows CE (!!), Blackberry, Windows, .Net, ... versions.

回答3:

If you're interested in the magic of Boost, check out Boost's stream filters which can be arbitrarily combined and cascaded; there's built-in support for gzip, DEFLATE (that's GZip minus the header) and bzip2. Very handy.