ZIP_SET_FILE_COMPRESS... BSD Library Functions Manual ZIP_SET_FILE_COMPRESS...
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 compres-
sion 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.
ZIP_CM_XZ Use the xz(1) algorithm for compression
ZIP_CM_ZSTD Use the zstd(1) algorithm for compression
NOTE: Only the deflate and store methods can be assumed to be universally
supported.
The comp_flags argument defines the compression level. This value is
dependent on the compression algorithm. In general, lower numbers mean
faster de/compression and higher numbers mean slower de/compression. For
ZIP_CM_BZIP, ZIP_CM_DEFLATE, and ZIP_CM_XZ 1 is the fastest compression
and 9 the best, 0 chooses the default. For ZIP_CM_ZSTD possible values
are ZSTD_minCLevel(3) to ZSTD_maxCLevel(3).
Further compression method specific flags might be added over time.
The current compression method for a file in a zip archive can be deter-
mined 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>
BSD June 18, 2021 BSD
libzip 1.8.0 - Generated Fri Jun 25 13:24:17 CDT 2021