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phpdeflate

PHP which compression function has equal output like mod_deflate?

I tried:

gzencode($contents, 9, FORCE_DEFLATE)
gzdeflate...
zlib_encode($contents, -15);// RFC 1951 - raw deflate
zlib_encode($contents, 15);// RFC 1950 - zlib

But none of them are suitable, because output is different.

And I'm talking about output, NOT headers!

I need deflate, not gzip.

Solution

  • PHP's gzcompress(). The use of the word "deflate" in the HTTP specification and content encoding is a misnomer. It really means zlib, which is a zlib wrapper around raw deflate data. gzcompress() produces zlib-wrapped deflate data.

    From the HTTP 1.1 specification:

    deflate: The "zlib" format defined in RFC 1950 [31] in combination with the "deflate" compression mechanism described in RFC 1951 [29].

    So HTTP "deflate" == zlib. HTTP "deflate" != deflate.

    For reference, gzencode() produces gzip-wrapped deflate data, and gzdeflate() produces raw, unwrapped deflate data.