ZIP_SOURCE_FILE(3) Introduction to Library Functions ZIP_SOURCE_FILE(3)
NAME
zip_source_file,
zip_source_file_create - create data source from a
file
LIBRARY
libzip (-lzip)
SYNOPSIS
#include <zip.h> zip_source_t * zip_source_file(
zip_t *archive,
const char *fname,
zip_uint64_t start,
zip_int64_t len);
zip_source_t * zip_source_file_create(
const char *fname,
zip_uint64_t start,
zip_int64_t len,
zip_error_t *error);
DESCRIPTION
The functions
zip_source_file() and
zip_source_file_create() create a
zip source from a file. They open
fname and read
len bytes from offset
start from it.
When passing ZIP_LENGTH_TO_END (or -1, which is deprecated) as
len,
zip_source_file determines the file size when it is called and uses
that as the expected file size. If the file size grows between
creating and reading from the source, the additional data is ignored.
If the file shrinks,
libzip treats it as an error (ZIP_ER_DATA_LENGTH).
When passing ZIP_LENGTH_UNCHECKED as
len,
zip_source_file assumes the
file's size is unknown. Reading from the source returns as much data
as is there at that time (usually when calling
zip_close(3)).
libzip can do various optimizations if the size of a source is known
when it's created, so ZIP_LENGTH_TO_END is preferrable. If you deal
with files that are likely to change while you are processing them, you
can use the less efficient ZIP_LENGTH_UNCHECKED.
If the file supports seek, the source can be used to open a zip archive
from.
The file is opened and read when the data from the source is used,
usually by
zip_close() or
zip_open_from_source().
RETURN VALUES
Upon successful completion, the created source is returned. Otherwise,
NULL is returned and the error code in
archive or
error is set to
indicate the error.
ERRORS
zip_source_file() and
zip_source_file_create() fail if:
[ZIP_ER_INVAL]
fname,
start, or
len are invalid.
[ZIP_ER_MEMORY] Required memory could not be allocated.
[ZIP_ER_OPEN] Opening
fname failed.
SEE ALSO
libzip(3),
zip_file_add(3),
zip_file_replace(3),
zip_source(3)HISTORY
zip_source_file() and
zip_source_file_create() were added in libzip
1.0.
ZIP_LENGTH_TO_END and ZIP_LENGTH_UNCHECKED were added in libzip 1.10.1.
AUTHORS
Dieter Baron <
dillo@nih.at> and Thomas Klausner <
wiz@gatalith.at>
illumos June 30, 2023 illumos
