.TH ARCHIVE_READ_EXTRACT 3 "February 2, 2012" ""

.SH NAME

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\fB\%archive_read_extract\fP,

\fB\%archive_read_extract2\fP,

\fB\%archive_read_extract_set_progress_callback\fP

\- functions for reading streaming archives

.SH LIBRARY

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Streaming Archive Library (libarchive, -larchive)

.SH SYNOPSIS

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\fB#include <archive.h>\fP

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\fIint\fP

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\fB\%archive_read_extract\fP(\fI\%struct\ archive\ *\fP, \fI\%struct\ archive_entry\ *\fP, \fI\%int\ flags\fP);

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\fIint\fP

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\fB\%archive_read_extract2\fP(\fI\%struct\ archive\ *src\fP, \fI\%struct\ archive_entry\ *\fP, \fI\%struct\ archive\ *dest\fP);

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\fIvoid\fP

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\fB\%archive_read_extract_set_progress_callback\fP(\fI\%struct\ archive\ *\fP, \fI\%void\ (*func)(void\ *)\fP, \fI\%void\ *user_data\fP);

.SH DESCRIPTION

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.RS 5

.TP

\fB\%archive_read_extract\fP(), \fB\%archive_read_extract_set_skip_file\fP()

A convenience function that wraps the corresponding

\fBarchive_write_disk\fP(3)

interfaces.

The first call to

\fB\%archive_read_extract\fP()

creates a restore object using

\fBarchive_write_disk_new\fP(3)

and

\fBarchive_write_disk_set_standard_lookup\fP(3),

then transparently invokes

\fBarchive_write_disk_set_options\fP(3),

\fBarchive_write_header\fP(3),

\fBarchive_write_data\fP(3),

and

\fBarchive_write_finish_entry\fP(3)

to create the entry on disk and copy data into it.

The

\fIflags\fP

argument is passed unmodified to

\fBarchive_write_disk_set_options\fP(3).

.TP

\fB\%archive_read_extract2\fP()

This is another version of

\fB\%archive_read_extract\fP()

that allows you to provide your own restore object.

In particular, this allows you to override the standard lookup functions

using

\fBarchive_write_disk_set_group_lookup\fP(3),

and

\fBarchive_write_disk_set_user_lookup\fP(3).

Note that

\fB\%archive_read_extract2\fP()

does not accept a

\fIflags\fP

argument; you should use

\fB\%archive_write_disk_set_options\fP()

to set the restore options yourself.

.TP

\fB\%archive_read_extract_set_progress_callback\fP()

Sets a pointer to a user-defined callback that can be used

for updating progress displays during extraction.

The progress function will be invoked during the extraction of large

regular files.

The progress function will be invoked with the pointer provided to this call.

Generally, the data pointed to should include a reference to the archive

object and the archive_entry object so that various statistics

can be retrieved for the progress display.

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.SH RETURN VALUES

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Most functions return zero on success, non-zero on error.

The possible return codes include:

\fBARCHIVE_OK\fP

(the operation succeeded),

\fBARCHIVE_WARN\fP

(the operation succeeded but a non-critical error was encountered),

\fBARCHIVE_EOF\fP

(end-of-archive was encountered),

\fBARCHIVE_RETRY\fP

(the operation failed but can be retried),

and

\fBARCHIVE_FATAL\fP

(there was a fatal error; the archive should be closed immediately).

.SH ERRORS

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Detailed error codes and textual descriptions are available from the

\fB\%archive_errno\fP()

and

\fB\%archive_error_string\fP()

functions.

.SH SEE ALSO

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\fBtar\fP(1),

\fBlibarchive\fP(3),

\fBarchive_read\fP(3),

\fBarchive_read_data\fP(3),

\fBarchive_read_filter\fP(3),

\fBarchive_read_format\fP(3),

\fBarchive_read_open\fP(3),

\fBarchive_read_set_options\fP(3),

\fBarchive_util\fP(3),

\fBtar\fP(5)