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ARCHIVE_READ_DATA(3)	     Library Functions Manual	    ARCHIVE_READ_DATA(3)

NAME
     archive_read_data,     archive_read_data_block,	 archive_read_data_skip,
     archive_read_data_into_fd -- functions for reading streaming archives

LIBRARY
     Streaming Archive Library (libarchive, -larchive)

SYNOPSIS
     #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);

DESCRIPTION
     archive_read_data()
	     Read data associated with the header just read.   Internally,  this
	     is  a convenience function that calls archive_read_data_block() and
	     fills any gaps with nulls so that callers see a  single  continuous
	     stream of data.
     archive_read_data_block()
	     Return  the  next	available  block of data for this entry.  Unlike
	     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()
	     A	   convenience	   function	 that	   repeatedly	   calls
	     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 com-
	     pletely consumed.
     archive_read_data_into_fd()
	     A	   convenience	   function	 that	   repeatedly	   calls
	     archive_read_data_block()	to copy the entire entry to the provided
	     file descriptor.

RETURN VALUES
     Most functions return zero on success, non-zero on error.	The possible re-
     turn 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.

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

SEE ALSO
     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)

FreeBSD ports 15.quarterly	February 2, 2012	    ARCHIVE_READ_DATA(3)

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