ARCHIVE_READ_DATA(3) | Library Functions Manual | ARCHIVE_READ_DATA(3) |
archive_read_data
,
archive_read_data_block
,
archive_read_data_skip
,
archive_read_data_into_fd
—
functions for reading streaming archives
Streaming Archive Library (libarchive, -larchive)
#include
<archive.h>
la_ssize_t
archive_read_data
(struct
archive *, void
*buff, size_t
len);
int
archive_read_data_block
(struct archive
*, const void **buff, size_t
*len, off_t *offset);
int
archive_read_data_skip
(struct
archive *);
int
archive_read_data_into_fd
(struct
archive *, int
fd);
archive_read_data
()archive_read_data_block
()
and fills any gaps with nulls so that callers see a single continuous
stream of data.archive_read_data_block
()archive_read_data
(), the
archive_read_data_block
() function avoids copying
data and allows you to correctly handle sparse files, as supported by some
archive formats. The library guarantees that offsets will increase and
that blocks will not overlap. Note that the blocks returned from this
function can be much larger than the block size read from disk, due to
compression and internal buffer optimizations.archive_read_data_skip
()archive_read_data_block
() to skip all of the data
for this archive entry. Note that this function is invoked automatically
by
archive_read_next_header2
()
if the previous entry was not completely consumed.archive_read_data_into_fd
()archive_read_data_block
() to copy the entire entry
to the provided file descriptor.Most functions return zero on success, non-zero on error. The
possible return codes include: ARCHIVE_OK
(the
operation succeeded), ARCHIVE_WARN
(the operation
succeeded but a non-critical error was encountered),
ARCHIVE_EOF
(end-of-archive was encountered),
ARCHIVE_RETRY
(the operation failed but can be
retried), and ARCHIVE_FATAL
(there was a fatal
error; the archive should be closed immediately).
archive_read_data
() returns a count of
bytes actually read or zero at the end of the entry. On error, a value of
ARCHIVE_FATAL
, ARCHIVE_WARN
,
or ARCHIVE_RETRY
is returned.
Detailed error codes and textual descriptions are available from
the archive_errno
() and
archive_error_string
() functions.
tar(1), archive_read(3), archive_read_extract(3), archive_read_filter(3), archive_read_format(3), archive_read_header(3), archive_read_open(3), archive_read_set_options(3), archive_util(3), libarchive(3), tar(5)
February 2, 2012 | macOS 14.6 |