source-git / libarchive

Clone
Source Code
GIT

Blame doc/html/archive_write.3.html

c8 c8s master
  1.   cc8190ec3d70c1de180e29fbbd40106e3d7cc46b
  2.   doc
  3.   html
  4.   archive_write.3.html
Blob History Raw
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
"http://www.w3.org/TR/html4/loose.dtd">
Packit Service 1d0348 
<html>
Packit Service 1d0348 
<head>
Packit Service 1d0348 
<meta name="generator" content="groff -Thtml, see www.gnu.org">
Packit Service 1d0348 
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
Packit Service 1d0348 
<meta name="Content-Style" content="text/css">
Packit Service 1d0348 
<style type="text/css">
Packit Service 1d0348 
       p       { margin-top: 0; margin-bottom: 0; vertical-align: top }
Packit Service 1d0348 
       pre     { margin-top: 0; margin-bottom: 0; vertical-align: top }
Packit Service 1d0348 
       table   { margin-top: 0; margin-bottom: 0; vertical-align: top }
Packit Service 1d0348 
       h1      { text-align: center }
Packit Service 1d0348 
</style>
Packit Service 1d0348 
<title></title>
Packit Service 1d0348 
</head>
Packit Service 1d0348 
<body>
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
ARCHIVE_WRITE(3) BSD Library Functions Manual
Packit Service 1d0348 
ARCHIVE_WRITE(3)
Packit Service 1d0348
Packit Service 1d0348 
NAME
Packit Service 1d0348
Packit Service 1d0348 
archive_write —
Packit Service 1d0348 
functions for creating archives
Packit Service 1d0348
Packit Service 1d0348 
LIBRARY
Packit Service 1d0348
Packit Service 1d0348 
Streaming Archive Library
Packit Service 1d0348 
(libarchive, -larchive)
Packit Service 1d0348
Packit Service 1d0348 
SYNOPSIS
Packit Service 1d0348
Packit Service 1d0348 
#include
Packit Service 1d0348 
<archive.h>
Packit Service 1d0348
Packit Service 1d0348 
DESCRIPTION
Packit Service 1d0348
Packit Service 1d0348 
These functions provide a
Packit Service 1d0348 
complete API for creating streaming archive files. The
Packit Service 1d0348 
general process is to first create the struct archive
Packit Service 1d0348 
object, set any desired options, initialize the archive,
Packit Service 1d0348 
append entries, then close the archive and release all
Packit Service 1d0348 
resources.
Packit Service 1d0348
Packit Service 1d0348 
Create
Packit Service 1d0348 
archive object
Packit Service 1d0348 
See archive_write_new(3).
Packit Service 1d0348
Packit Service 1d0348 
To write an
Packit Service 1d0348 
archive, you must first obtain an initialized struct archive
Packit Service 1d0348 
object from archive_write_new().
Packit Service 1d0348
Packit Service 1d0348 
Enable
Packit Service 1d0348 
filters and formats, configure block size and padding
Packit Service 1d0348

Packit Service 1d0348 
See archive_write_filter(3), archive_write_format(3) and
Packit Service 1d0348 
archive_write_blocksize(3).
Packit Service 1d0348
Packit Service 1d0348 
You can then
Packit Service 1d0348 
modify this object for the desired operations with the
Packit Service 1d0348 
various archive_write_set_XXX() functions. In
Packit Service 1d0348 
particular, you will need to invoke appropriate
Packit Service 1d0348 
archive_write_add_XXX() and
Packit Service 1d0348 
archive_write_set_XXX() functions to enable the
Packit Service 1d0348 
corresponding compression and format support.
Packit Service 1d0348
Packit Service 1d0348 
Set
Packit Service 1d0348 
options
Packit Service 1d0348 
See archive_write_set_options(3).
Packit Service 1d0348
Packit Service 1d0348 
Open
Packit Service 1d0348 
archive
Packit Service 1d0348 
See archive_write_open(3).
Packit Service 1d0348
Packit Service 1d0348 
Once you have
Packit Service 1d0348 
prepared the struct archive object, you call
Packit Service 1d0348 
archive_write_open() to actually open the archive and
Packit Service 1d0348 
prepare it for writing. There are several variants of this
Packit Service 1d0348 
function; the most basic expects you to provide pointers to
Packit Service 1d0348 
several functions that can provide blocks of bytes from the
Packit Service 1d0348 
archive. There are convenience forms that allow you to
Packit Service 1d0348 
specify a filename, file descriptor, FILE * object,
Packit Service 1d0348 
or a block of memory from which to write the archive
Packit Service 1d0348 
data.
Packit Service 1d0348
Packit Service 1d0348 
Produce
Packit Service 1d0348 
archive
Packit Service 1d0348 
See archive_write_header(3) and archive_write_data(3).
Packit Service 1d0348
Packit Service 1d0348 
Individual
Packit Service 1d0348 
archive entries are written in a three-step process: You
Packit Service 1d0348 
first initialize a struct archive_entry structure with
Packit Service 1d0348 
information about the new entry. At a minimum, you should
Packit Service 1d0348 
set the pathname of the entry and provide a struct
Packit Service 1d0348 
stat with a valid st_mode field, which specifies
Packit Service 1d0348 
the type of object and st_size field, which specifies
Packit Service 1d0348 
the size of the data portion of the object.
Packit Service 1d0348
Packit Service 1d0348 
Release
Packit Service 1d0348 
resources
Packit Service 1d0348 
See archive_write_free(3).
Packit Service 1d0348
Packit Service 1d0348 
After all
Packit Service 1d0348 
entries have been written, use the
Packit Service 1d0348 
archive_write_free() function to release all
Packit Service 1d0348 
resources.
Packit Service 1d0348
Packit Service 1d0348 
EXAMPLE
Packit Service 1d0348
Packit Service 1d0348 
The following sketch illustrates
Packit Service 1d0348 
basic usage of the library. In this example, the callback
Packit Service 1d0348 
functions are simply wrappers around the standard open(2),
Packit Service 1d0348 
write(2), and close(2) system calls.
Packit Service 1d0348
Packit Service 1d0348 
#ifdef
Packit Service 1d0348 
__linux__
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
       cellspacing="0" cellpadding="0">
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
#define
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
_FILE_OFFSET_BITS 64
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348
Packit Service 1d0348 
#endif
Packit Service 1d0348 
#include <sys/stat.h>
Packit Service 1d0348 
#include <archive.h>
Packit Service 1d0348 
#include <archive_entry.h>
Packit Service 1d0348 
#include <fcntl.h>
Packit Service 1d0348 
#include <stdlib.h>
Packit Service 1d0348 
#include <unistd.h>
Packit Service 1d0348
Packit Service 1d0348 
struct mydata {
Packit Service 1d0348

Packit Service 1d0348 
const char *name;
Packit Service 1d0348 
int fd;
Packit Service 1d0348 
};
Packit Service 1d0348
Packit Service 1d0348 
int
Packit Service 1d0348 
myopen(struct archive *a, void *client_data)
Packit Service 1d0348 
{
Packit Service 1d0348 
struct mydata *mydata = client_data;
Packit Service 1d0348
Packit Service 1d0348 
mydata->fd =
Packit Service 1d0348 
open(mydata->name, O_WRONLY | O_CREAT, 0644);
Packit Service 1d0348 
if (mydata->fd >= 0)
Packit Service 1d0348 
return (ARCHIVE_OK);
Packit Service 1d0348 
else
Packit Service 1d0348 
return (ARCHIVE_FATAL);
Packit Service 1d0348 
}
Packit Service 1d0348
Packit Service 1d0348 
la_ssize_t
Packit Service 1d0348 
mywrite(struct archive *a, void *client_data, const void
Packit Service 1d0348 
*buff, size_t n)
Packit Service 1d0348 
{
Packit Service 1d0348 
struct mydata *mydata = client_data;
Packit Service 1d0348
Packit Service 1d0348 
return
Packit Service 1d0348 
(write(mydata->fd, buff, n));
Packit Service 1d0348 
}
Packit Service 1d0348
Packit Service 1d0348 
int
Packit Service 1d0348 
myclose(struct archive *a, void *client_data)
Packit Service 1d0348 
{
Packit Service 1d0348 
struct mydata *mydata = client_data;
Packit Service 1d0348
Packit Service 1d0348 
if
Packit Service 1d0348 
(mydata->fd > 0)
Packit Service 1d0348 
close(mydata->fd);
Packit Service 1d0348 
return (0);
Packit Service 1d0348 
}
Packit Service 1d0348
Packit Service 1d0348 
void
Packit Service 1d0348 
write_archive(const char *outname, const char **filename)
Packit Service 1d0348

Packit Service 1d0348 
{
Packit Service 1d0348 
struct mydata *mydata = malloc(sizeof(struct mydata));
Packit Service 1d0348 
struct archive *a;
Packit Service 1d0348 
struct archive_entry *entry;
Packit Service 1d0348 
struct stat st;
Packit Service 1d0348 
char buff[8192];
Packit Service 1d0348 
int len;
Packit Service 1d0348 
int fd;
Packit Service 1d0348
Packit Service 1d0348 
a =
Packit Service 1d0348 
archive_write_new();
Packit Service 1d0348 
mydata->name = outname;
Packit Service 1d0348 
/* Set archive format and filter according to output file
Packit Service 1d0348 
extension.
Packit Service 1d0348 
* If it fails, set default format. Platform depended
Packit Service 1d0348 
function.
Packit Service 1d0348 
* See supported formats in
Packit Service 1d0348 
archive_write_set_format_filter_by_ext.c */
Packit Service 1d0348 
if (archive_write_set_format_filter_by_ext(a, outname) !=
Packit Service 1d0348 
ARCHIVE_OK) {
Packit Service 1d0348 
archive_write_add_filter_gzip(a);
Packit Service 1d0348 
archive_write_set_format_ustar(a);
Packit Service 1d0348 
}
Packit Service 1d0348 
archive_write_open(a, mydata, myopen, mywrite, myclose);
Packit Service 1d0348

Packit Service 1d0348 
while (*filename) {
Packit Service 1d0348 
stat(*filename, &st);
Packit Service 1d0348 
entry = archive_entry_new();
Packit Service 1d0348 
archive_entry_copy_stat(entry, &st);
Packit Service 1d0348 
archive_entry_set_pathname(entry, *filename);
Packit Service 1d0348 
archive_write_header(a, entry);
Packit Service 1d0348 
if ((fd = open(*filename, O_RDONLY)) != -1) {
Packit Service 1d0348 
len = read(fd, buff, sizeof(buff));
Packit Service 1d0348 
while (len > 0) {
Packit Service 1d0348 
archive_write_data(a, buff, len);
Packit Service 1d0348 
len = read(fd, buff, sizeof(buff));
Packit Service 1d0348 
}
Packit Service 1d0348 
close(fd);
Packit Service 1d0348 
}
Packit Service 1d0348 
archive_entry_free(entry);
Packit Service 1d0348 
filename++;
Packit Service 1d0348 
}
Packit Service 1d0348 
archive_write_free(a);
Packit Service 1d0348 
}
Packit Service 1d0348
Packit Service 1d0348 
int main(int
Packit Service 1d0348 
argc, const char **argv)
Packit Service 1d0348 
{
Packit Service 1d0348 
const char *outname;
Packit Service 1d0348 
argv++;
Packit Service 1d0348 
outname = *argv++;
Packit Service 1d0348 
write_archive(outname, argv);
Packit Service 1d0348 
return 0;
Packit Service 1d0348 
}
Packit Service 1d0348
Packit Service 1d0348 
SEE ALSO
Packit Service 1d0348
Packit Service 1d0348 
tar(1), libarchive(3),
Packit Service 1d0348 
archive_write_set_options(3), cpio(5), mtree(5), tar(5)
Packit Service 1d0348
Packit Service 1d0348 
HISTORY
Packit Service 1d0348
Packit Service 1d0348 
The libarchive library
Packit Service 1d0348 
first appeared in FreeBSD 5.3.
Packit Service 1d0348
Packit Service 1d0348 
AUTHORS
Packit Service 1d0348
Packit Service 1d0348 
The libarchive library
Packit Service 1d0348 
was written by Tim Kientzle <kientzle@acm.org>.
Packit Service 1d0348
Packit Service 1d0348 
BUGS
Packit Service 1d0348
Packit Service 1d0348 
There are many peculiar bugs in
Packit Service 1d0348 
historic tar implementations that may cause certain programs
Packit Service 1d0348 
to reject archives written by this library. For example,
Packit Service 1d0348 
several historic implementations calculated header checksums
Packit Service 1d0348 
incorrectly and will thus reject valid archives; GNU tar
Packit Service 1d0348 
does not fully support pax interchange format; some old tar
Packit Service 1d0348 
implementations required specific field terminations.
Packit Service 1d0348
Packit Service 1d0348 
The default pax
Packit Service 1d0348 
interchange format eliminates most of the historic tar
Packit Service 1d0348 
limitations and provides a generic key/value attribute
Packit Service 1d0348 
facility for vendor-defined extensions. One oversight in
Packit Service 1d0348 
POSIX is the failure to provide a standard attribute for
Packit Service 1d0348 
large device numbers. This library uses
Packit Service 1d0348 
’’SCHILY.devminor’’ and
Packit Service 1d0348 
’’SCHILY.devmajor’’ for device
Packit Service 1d0348 
numbers that exceed the range supported by the
Packit Service 1d0348 
backwards-compatible ustar header. These keys are compatible
Packit Service 1d0348 
with Joerg Schilling’s star archiver. Other
Packit Service 1d0348 
implementations may not recognize these keys and will thus
Packit Service 1d0348 
be unable to correctly restore device nodes with large
Packit Service 1d0348 
device numbers from archives created by this library.
Packit Service 1d0348
Packit Service 1d0348 
BSD
Packit Service 1d0348 
February 2, 2012 BSD
Packit Service 1d0348
Packit Service 1d0348 
</body>
Packit Service 1d0348 
</html>

Powered by Pagure 5.14.1

SSH Hostkey/Fingerprint | Documentation