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man pages section 3: Extended Library Functions, Volume 1

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Updated: Wednesday, July 27, 2022
 
 

archive_write_open (3archive)

Name

archive_write_open - archive_write_open, archive_write_open2, archive_write_open_fd, archive_write_open_FILE, archive_write_open_filename, functions for creating archives

Synopsis

#include <archive.h>
int
archive_write_open(struct archive *, void *client_data,
archive_open_callback *, archive_write_callback *,
archive_close_callback *);
int
archive_write_open2(struct archive *, void *client_data,
archive_open_callback *, archive_write_callback *,
archive_close_callback *, archive_free_callback *);
int
archive_write_open_fd(struct archive *, int fd);
int
archive_write_open_FILE(struct archive *, FILE *file);
int
archive_write_open_filename(struct archive *, const char *filename);
int
archive_write_open_memory(struct archive *, void *buffer,
size_t bufferSize, size_t *outUsed);

Description

                                                  ARCHIVE_WRITE_OPEN(3archive)



NAME
       archive_write_open, archive_write_open2, archive_write_open_fd,
       archive_write_open_FILE, archive_write_open_filename,
       archive_write_open_memory - functions for creating archives

LIBRARY
       Streaming Archive Library (libarchive, -larchive)

SYNOPSIS
       #include <archive.h>
       int
       archive_write_open(struct archive *, void *client_data,
       archive_open_callback *, archive_write_callback *,
       archive_close_callback *);
       int
       archive_write_open2(struct archive *, void *client_data,
       archive_open_callback *, archive_write_callback *,
       archive_close_callback *, archive_free_callback *);
       int
       archive_write_open_fd(struct archive *, int fd);
       int
       archive_write_open_FILE(struct archive *, FILE *file);
       int
       archive_write_open_filename(struct archive *, const char *filename);
       int
       archive_write_open_memory(struct archive *, void *buffer,
       size_t bufferSize, size_t *outUsed);

DESCRIPTION
            archive_write_open()
                   Freeze the settings, open the archive, and prepare for
                   writing entries.  This is the most generic form of this
                   function, which accepts pointers to three callback func-
                   tions which will be invoked by the compression layer to
                   write the constructed archive.  This does not alter the
                   default archive padding.

            archive_write_open2()
                   Same as archive_write_open() with an additional fourth free
                   callback. This function should be preferred to
                   archive_write_open().

            archive_write_open_fd()
                   A convenience form of archive_write_open() that accepts a
                   file descriptor.  The archive_write_open_fd() function is
                   safe for use with tape drives or other block-oriented
                   devices.

            archive_write_open_FILE()
                   A convenience form of archive_write_open() that accepts a
                   FILE * pointer.  Note that archive_write_open_FILE() is not
                   safe for writing to tape drives or other devices that
                   require correct blocking.

            archive_write_open_file()
                   A deprecated synonym for archive_write_open_filename().

            archive_write_open_filename()
                   A convenience form of archive_write_open() that accepts a
                   filename.  A NULL argument indicates that the output should
                   be written to standard output; an argument of ``-'' will
                   open a file with that name.  If you have not invoked
                   archive_write_set_bytes_in_last_block(), then
                   archive_write_open_filename() will adjust the last-block
                   padding depending on the file: it will enable padding when
                   writing to standard output or to a character or block
                   device node, it will disable padding otherwise.  You can
                   override this by manually invoking
                   archive_write_set_bytes_in_last_block() before calling
                   archive_write_open2().  The archive_write_open_filename()
                   function is safe for use with tape drives or other block-
                   oriented devices.

            archive_write_open_memory()
                   A convenience form of archive_write_open2() that accepts a
                   pointer to a block of memory that will receive the archive.
                   The final size_t * argument points to a variable that will
                   be updated after each write to reflect how much of the buf-
                   fer is currently in use.  You should be careful to ensure
                   that this variable remains allocated until after the ar-
                   chive is closed.  This function will disable padding unless
                   you have specifically set the block size.
       More information about the struct archive object and the overall design
       of the library can be found in the libarchive(3) overview.

       Note that the convenience forms above vary in how they block the out-
       put.  See archive_write_blocksize(3) if you need to control the block
       size used for writes or the end-of-file padding behavior.

CLIENT CALLBACKS
       To use this library, you will need to define and register callback
       functions that will be invoked to write data to the resulting archive.
       These functions are registered by calling archive_write_open2():

                   typedef int archive_open_callback(struct archive *,
                   void *client_data)

       The open callback is invoked by archive_write_open().  It should return
       ARCHIVE_OK if the underlying file or data source is successfully
       opened.  If the open fails, it should call archive_set_error() to reg-
       ister an error code and message and return ARCHIVE_FATAL.  Please note
       that if open fails, close is not called and resources must be freed
       inside the open callback or with the free callback.

                   typedef la_ssize_t archive_write_callback(struct archive *,
                   void *client_data, const void *buffer, size_t length)

       The write callback is invoked whenever the library needs to write raw
       bytes to the archive.  For correct blocking, each call to the write
       callback function should translate into a single write(2) system call.
       This is especially critical when writing archives to tape drives.  On
       success, the write callback should return the number of bytes actually
       written.  On error, the callback should invoke archive_set_error() to
       register an error code and message and return -1.

                   typedef int archive_close_callback(struct archive *,
                   void *client_data)

       The close callback is invoked by archive_close when the archive pro-
       cessing is complete. If the open callback fails, the close callback is
       not invoked.  The callback should return ARCHIVE_OK on success.  On
       failure, the callback should invoke archive_set_error() to register an
       error code and message and return

                   typedef int archive_free_callback(struct archive *,
                   void *client_data)

       The free callback is always invoked on archive_free.  The return code
       of this callback is not processed.

       Note that if the client-provided write callback function returns a non-
       zero value, that error will be propagated back to the caller through
       whatever API function resulted in that call, which may include
       archive_write_header(), archive_write_data(), archive_write_close(),
       archive_write_finish(), or archive_write_free().  The client callback
       can call archive_set_error() to provide values that can then be
       retrieved by archive_errno() and archive_error_string().

RETURN VALUES
       These functions return ARCHIVE_OK on success, or ARCHIVE_FATAL.

ERRORS
       Detailed error codes and textual descriptions are available from the
       archive_errno() and archive_error_string() functions.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+--------------------+
       |ATTRIBUTE TYPE |  ATTRIBUTE VALUE   |
       +---------------+--------------------+
       |Availability   | library/libarchive |
       +---------------+--------------------+
       |Stability      | Uncommitted        |
       +---------------+--------------------+

SEE ALSO
       tar(1), archive_write(3), archive_write_blocksize(3), ar-
       chive_write_filter(3), archive_write_format(3), archive_write_new(3),
       archive_write_set_options(3), libarchive(3), mtree(5)



NOTES
       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       https://github.com/libarchive/libarchive/releases/down-
       load/v3.6.1/libarchive-3.6.1.tar.gz.

       Further information about this software can be found on the open source
       community website at http://www.libarchive.org/.



                               November 12, 2020
                                                  ARCHIVE_WRITE_OPEN(3archive)