| ZIP_SET_FILE_COMPRESSION(3) | Library Functions Manual | ZIP_SET_FILE_COMPRESSION(3) |
zip_set_file_compression —
set compression method for file in zip
libzip (-lzip)
#include
<zip.h>
int
zip_set_file_compression(zip_t
*archive, zip_uint64_t
index, zip_int32_t
comp, zip_uint32_t
comp_flags);
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_DEFAULTZIP_CM_DEFLATE, but flags
are ignored.ZIP_CM_STOREZIP_CM_BZIP2ZIP_CM_DEFLATEZIP_CM_XZZIP_CM_ZSTDNOTE: 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); negative
values must be cast to zip_uint32_t.
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).
Upon successful completion 0 is returned. Otherwise, -1 is returned and the error information in archive is set to indicate the error.
zip_set_file_compression() fails if:
ZIP_ER_COMPNOTSUPP]ZIP_ER_INVAL]ZIP_ER_RDONLY]zip_set_file_compression() was added in
libzip 0.11.
Dieter Baron <dillo@nih.at> and Thomas Klausner <wiz@gatalith.at>
| February 2, 2023 | NiH |