gzwrite() writes the contents of
string to the gz-file
stream pointed to by zp. If
the length argument is
given, writing will stop after
length (uncompressed) bytes have been written or the
end of string is reached,
whichever comes first.
gzwrite() returns the number of
(uncompressed) bytes written to the gz-file stream pointed to
by zp.
Note that if the
length argument is given, then the
magic_quotes_runtime configuration option will be ignored
and no slashes will be stripped from
string.