tar_extract_file

Section: C Library Calls (3)
Updated: Jan 2001
Page Index

NAME

tar_extract_file, tar_extract_regfile, tar_extract_hardlink, tar_extract_symlink, tar_extract_chardev, tar_extract_blockdev, tar_extract_dir, tar_extract_fifo, tar_skip_regfile, tar_set_file_perms - extract files from a tar archive

SYNOPSIS

#include <libtar.h>

int tar_extract_file(TAR *t, char *realname);

int tar_extract_regfile(TAR *t, char *realname);

int tar_skip_regfile(TAR *t);

int tar_extract_dir(TAR *t, char *realname);

int tar_extract_hardlink(TAR *t, char *realname);

int tar_extract_symlink(TAR *t, char *realname);

int tar_extract_blockdev(TAR *t, char *realname);

int tar_extract_chardev(TAR *t, char *realname);

int tar_extract_fifo(TAR *t, char *realname);

int tar_set_file_perms(TAR *t, char *realname);

VERSION

This man page documents version 1.2 of libtar.

DESCRIPTION

The tar_extract_file() function acts as a front-end to the other tar_extract_*() functions. It checks the current tar header associated with the TAR handle t (which must be initialized first by calling th_read()) to determine what kind of file the header refers to. It then calls the appropriate tar_extract_*() function to extract that kind of file.

The tar_skip_regfile() function skips over the file content blocks and positions the file pointer at the expected location of the next tar header block.

The tar_set_file_perms() function sets the attributes of the extracted file to match the encoded values. This includes the file's modification time, mode, owner, and group. This function is automatically called by tar_extract_file(), but applications which call the other tar_extract_*() functions directly will need to call tar_set_file_perms() manually if this behavior is desired.

RETURN VALUES

On successful completion, the functions documented here will return 0. On failure, they will return -1 and set errno to an appropriate value.

The tar_extract_dir() function will return 1 if the directory already exists.

ERRORS

The tar_extract_file() function will fail if:

EEXIST: If the O_NOOVERWRITE flag is set and the file already exists.

The tar_extract_*() functions will fail if:

EINVAL: An entry could not be added to the internal file hash.
EINVAL: Less than T_BLOCKSIZE bytes were read from the tar archive.
EINVAL: The current file header associated with t refers to a kind of file other than the one which the called function knows about.

They may also fail if any of the following functions fail: mkdir(), write(), link(), symlink(), mknod(), mkfifo(), utime(), chown(), lchown(), chmod(), or lstat().