NAME

     zip_set_file_compression — set compression method for file in zip

LIBRARY

     libzip (-lzip)

SYNOPSIS

     #include <zip.h>

     int
     zip_set_file_compression(zip_t *archive, zip_uint64_t index, zip_int32_t comp,
         zip_uint32_t comp_flags);

DESCRIPTION

     The zip_set_file_compression() function sets the compression method for the file at position
     index in the zip archive to comp with the compression method specific comp_flags.  The comp
     is the same as returned by zip_stat(3).  For the comp argument, currently only the following
     values are supported:

     ZIP_CM_DEFAULT     default compression; currently the same as ZIP_CM_DEFLATE, but flags are
                        ignored.

     ZIP_CM_STORE       Store the file uncompressed.

     ZIP_CM_BZIP2       Compress the file using the bzip2(1) algorithm.

     ZIP_CM_DEFLATE     Deflate the file with the zlib(3) algorithm and default options.

     NOTE: Only the deflate and store methods can be assumed to be universally supported.

     The comp_flags argument defines the compression level, 1 being fastest compression and 9
     highest.  Allowed values are 0 (which uses the default compression for the algorithm) and
     1-9, other values are undefined.  Further compression method specific flags might be added
     over time.

     The current compression method for a file in a zip archive can be determined using
     zip_stat(3).

RETURN VALUES

     Upon successful completion 0 is returned.  Otherwise, -1 is returned and the error
     information in archive is set to indicate the error.

ERRORS

     zip_set_file_compression() fails if:

     [ZIP_ER_COMPNOTSUPP]
                        Unsupported compression method requested.

     [ZIP_ER_INVAL]     index is not a valid file index in archive, or the argument combination
                        is invalid.

     [ZIP_ER_RDONLY]    Read-only zip file, no changes allowed.

SEE ALSO

     libzip(3), zip_compression_method_supported(3), zip_stat(3)

HISTORY

     zip_set_file_compression() was added in libzip 0.11.

AUTHORS

     Dieter Baron <dillo@nih.at> and Thomas Klausner <tk@giga.or.at>