ZIP_SET_FILE_COMPRESSION(3) | Library Functions Manual | ZIP_SET_FILE_COMPRESSION(3) |
zip_set_file_compression
—
#include <zip.h>
int
zip_set_file_compression
(zip_t
*archive, zip_uint64_t
index, zip_int32_t
comp, zip_uint32_t
comp_flags);
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
ZIP_CM_DEFLATE
, but flags
are ignored.ZIP_CM_STORE
ZIP_CM_BZIP2
ZIP_CM_DEFLATE
ZIP_CM_XZ
ZIP_CM_ZSTD
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 determined using zip_stat(3).
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.
June 18, 2021 | NiH |