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Committer: Bazaar Package Importer
Author(s): Dirk Eddelbuettel
Date: 2002-03-14 10:30:49 UTC
Revision ID: james.westby@ubuntu.com-20020314103049-nifwa0xp6x1g63bu

Tags: upstream-2.4.7

Import upstream version 2.4.7

files added:

HISTORY

INSTALLATION

Makefile

PORTING

README

SCRIPTS

afio.1

afio.c

afio.h

afio.lsm

compfile.c

exten.c

gnu.fnmatch.tar.gz

match.c

patchlevel.h

perl.artistic.license

script1

script1/DONTDUMP

script1/backup

script2

script2/README

script2/backup

script2/restore

script2/x.dot

script2/x.home

script3

script3/gnupg_read

script3/gnupg_write

script3/pgp_read

script3/pgp_write

script4

script4/tapechange

script5

script5/secbak

script5/secrestore

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afio.1

'br $Header: /u/buhrt/src/afio/RCS/afio.1,v 2.3 1991/09/25 20:08:33 buhrt Exp $

.TH AFIO 1

.SH NAME

afio \- manipulate archives and files

.SH SYNOPSIS

.B ...

.B afio -o

[

.I options

] archive : write archive

.br

.B afio -i

[

.I options

] archive : install archive

.br

.B afio -t

[

.I options

] archive : list table-of-contents of archive

.br

.B afio -r

[

.I options

] archive : verify archive against filesystem

.br

.B afio -p

[

.I options

] directory [ ... ] : copy files

.PP

.SH DESCRIPTION

.I Afio

manipulates groups of files, copying them within the (collective)

filesystem or between the filesystem and an

.I afio

archive. Note that

.I afio

archives are portable, as they contain only ASCII-formatted

header information. They are also compatible with ASCII

.IR cpio (1)

archives (ala

.IR "cpio \-c" ,

for GNU

.IR cpio (1)

also

.IR "cpio -H odc" ).

However, archives made with using

.BR \-4

option are

.BR not

portable.

.PP

With

.BR \-o ,

reads pathnames from the standard input

and writes an

.IR archive .

.PP

With

.BR \-t ,

reads an

.I archive

and writes a table-of-contents to the standard output.

.PP

With

.BR \-i ,

installs the contents of an

.I archive

relative to the working directory.

.PP

With

.BR \-p ,

reads pathnames from the standard input

and copies the files to each

.IR directory .

Cannot be combined with the

.B \-Z

option.

.PP

With

.BR \-r ,

reads

.IR archive

and verifies it against the filesystem. This is useful for verifying

tape archives.

.PP

Creates missing directories as necessary, with permissions

to match their parents.

.PP

Removes leading slashes from pathnames when reading, writing, and cataloging

an archive, unless instructed not to.

.PP

Supports multi-volume archives during interactive operation

(i.e., when

.I /dev/tty

is accessible and

.I SIGINT

100

is not being ignored).

101

.PP

102

.SH OPTIONS

103

.TP 13

104

.BI "-@ " address

105

Send email to

106

.I address

107

when a volume change (tape change, floppy change) is needed, and also when

108

the entire operation is complete. Uses

109

.IR sendmail (1)

110

to send the mail.

111

.TP

112

.B -a

113

Preserve the last access times (atimes) of the files read when

114

making or verifying an archive.

115

.B Warning:

116

if this option is used,

117

.I afio

118

will change the last inode changed times (ctimes) of these files.

119

Thus, this option cannot be used together with an incremental backup

120

scheme that relies on the ctimes being preserved.

121

.TP

122

.BI \-b "\ size"

123

Read or write

124

.IR size -character

125

archive blocks.

126

Suffices of

127

.BR b ,

128

.BR k ,

129

.B m

130

and

131

.B g

132

denote multiples of

133

.IR 512 ,

134

.IR kilobytes ,

135

.IR megabytes

136

and

137

.IR gigabytes ,

138

respectively.

139

Defaults to

140

.I 5120

141

for compatibility with

142

.IR cpio (1).

143

In some cases, notably when using

144

.I ftape

145

with some tape drives,

146

.B \-b 10k

147

is needed for compatibility. Note that

148

.B \-b 10k

149

is the default block size used by

150

.IR tar (1),

151

so it is usually a good choice if the tape setup is known to work

152

with

153

.IR tar (1).

154

.TP

155

.BI \-c "\ count"

156

Buffer

157

.I count

158

archive blocks between I/O operations. A large

159

.I count

160

is recommended for efficient use with streaming magnetic tape drives, in

161

order to reduce the number of tape stops and restarts.

162

.TP

163

.B \-d

164

Don't create missing directories.

165

.TP

166

.BI \-e "\ bound"

167

Pad the archive to a multiple of

168

.I bound

169

characters.

170

Recognizes the same suffices as

171

.BR \-s .

172

Defaults to

173

.I 1x\^

174

(the

175

.B \-b

176

block size)

177

for compatibility with

178

.IR cpio (1).

179

.TP

180

.B \-f

181

Spawn a child process to actually write to the archive; provides

182

a clumsy form of double-buffering.

183

Requires

184

.B \-s

185

for multi-volume archive support.

186

.TP

187

.B \-g

188

Change to input file directories. Avoids quadratic filesystem

189

behavior with long similar pathnames. Requires all absolute

190

pathnames, including those for the

191

.B \-o

192

.I archive

193

and the

194

.B \-p

195

.IR directories .

196

.TP

197

.B \-h

198

Follow symbolic links, treating them as ordinary files and directories.

199

.TP

200

.B \-j

201

Don't generate sparse filesystem blocks on restoring files.

202

By default,

203

.I afio

204

creates sparse filesystem blocks (with

205

.IR lseek (2))

206

when possible when restoring files from an archive,

207

but not if these files were stored in a compressed form. Unless stored in

208

a compressed form, sparse files are not archived efficiently:

209

they will take space equal to the full file length.

210

(The sparse file handling in

211

.I afio

212

does not make much sense except in a historical way.)

213

.TP

214

.B \-k

215

Skip corrupt data at the

216

.I beginning

217

of an archive (rather

218

than complaining about unrecognizable input).

219

.TP

220

.B \-l

221

With

222

.BR \-o ,

223

write file contents with each hard link.

224

.sp

225

With

226

.BR \-t ,

227

report hard links.

228

.sp

229

With

230

.BR \-p ,

231

attempt to link files rather than copying them.

232

.TP

233

.B \-m

234

Mark output files with a common current timestamp

235

(rather than with input file modification times).

236

.TP

237

.B \-n

238

Protect newer existing files (comparing file modification times).

239

.TP

240

.BI \-s "\ size"

241

Restrict each portion of a multi-volume archive to

242

.I size

243

characters. This

244

option recognizes the same size suffices as

245

.BR \-b .

246

Also, the suffix

247

.B x

248

denotes a multiple of the

249

.B \-b

250

block size (and must follow any

251

.B \-b

252

specification).

253

.I size

254

can be a single size or a comma-seperated list of sizes,

255

for example '2m,5m,8m', to specify different sizes for the

256

subsequent volumes. If there are more volumes than sizes, the last

257

specified size is used for all remaining volumes.

258

This option is useful

259

with finite-length devices which do not return short

260

counts at end of media (sigh); output to magnetic tape typically

261

falls into this category. When an archive is being read or written, using

262

.B \-s

263

causes

264

.I afio

265

to prompt for the next volume if the specified volume length is reached.

266

The

267

.B \-s

268

option will also cause

269

.I afio

270

to prompt if there is a premature EOF while reading the input.

271

The special case

272

.B -s 0

273

will activate this prompting for the next volume on premature EOF without

274

setting a volume length.

275

When writing an archive,

276

.I afio

277

will prompt for the next volume on end-of-media, even without

278

.B -s 0

279

being supplied, if the device is capable of reporting end-of-media.

280

If the volume

281

.I size

282

specified is not a multiple of the block size set with the

283

.B -b

284

option, then

285

.I afio(1)

286

will silently round down the volume size to the nearest multiple of

287

the block size. This rounding down can be suppressed using the

288

.B -9

289

option: if

290

.B -9

291

is used,

292

.I afio(1)

293

will write a small block of data, smaller than the

294

.B -b

295

size, at the end of the volume to completely fill it to the specified

296

size. Some devices are not able to handle such small block writes.

297

.TP

298

.B \-u

299

Report files with unseen links.

300

.TP

301

.B \-v

302

Verbose. Report pathnames as they are processed. With

303

.BR \-t ,

304

gives an

305

.I "ls \-l"

306

style report (including link information).

307

.TP

308

.BI \-w "\ filename"

309

Treats each line in

310

.I filename

311

as an

312

.B \-y

313

pattern, see

314

.BR \-y .

315

.TP

316

.B \-x

317

Retain file ownership and setuid/setgid permissions.

318

This is the default for the super-user; he may use

319

.B \-X

320

to override it.

321

.TP

322

.BI \-y "\ pattern"

323

Restrict processing of files to names matching shell wildcard pattern

324

.IR pattern .

325

Use this flag once for each pattern to be recognized.

326

With the possible exception of the presence of a leading slash, the

327

complete file name as appearing in the archive table-of-contents must

328

match the pattern, for example the file name 'etc/passwd' is matched

329

by the pattern '*passwd' but NOT by the pattern 'passwd'. See

330

.B `man 7 glob'

331

for more information on shell wildcard pattern matching.

332

The only difference with shell wildcard pattern matching is that in

333

.I afio

334

the wildcards will also match '/' characters in file

335

names. For example the pattern '/usr/src/*' will match the

336

file name '/usr/src/linux/Makefile', and any other file name

337

starting with '/usr/src'. Unless the

338

.B -S

339

option is given, any leading slash in the pattern or the filename is

340

ignored when matching,

341

e.g.

342

.I /etc/passwd

343

will match

344

.IR etc/passwd .

345

Use

346

.B \-Y

347

to supply patterns which are

348

.I not

349

to be processed.

350

.B \-Y

351

overrides

352

.B \-y

353

if a filename matches both.

354

See also

606

.BR "\-y " and " -W" .

607

.TP

608

.B -Z

609

Gzip the files on the way out, in, and passing without links

610

(valid w/ or w/o

611

.BR -F "\ or" "\ -K" ),

612

requires

613

.IR gzip (1)

614

to be

615

in your path. See also the

616

.BR -G ,

617

.BR -P ,

618

.BR -Q ,

619

.BR -T ,

620

.BR -2 ,

621

and

622

.B -3

623

options.

624

.TP

625

.B -0

626

Assume input filenames to be terminated with a '\\0' instead

627

of a '\\n'. When used with

628

.IR "find ... -print0" ,

629

can be used to ensure that any filename can be handled,

630

even if it contains a newline.

631

.TP

632

.BI \-1 "\ warnings-to-ignore-on-exit"

633

Control if

634

.IR afio (1)

635

should exit with a nonzero code after printing warning messages.

636

This option is sometimes useful when calling

637

.IR afio (1)

638

from inside a backup script or program.

639

.IR afio (1)

640

will exit with a nonzero code on encountering

641

various 'hard' errors, and also (by default) when it has printed

642

certain warning messages during execution.

643

.I warnings-to-ignore-on-exit

644

is a list of letters which label the warning messages

645

that should

646

.B not

647

lead to

648

.IR afio (1)

649

exiting with a nonzero code.

650

Defined letters are

651

.I a

652

for ignoring

653

.IR a ll

654

possible warnings on exit, and

655

.I m

656

for ignoring the warning about

657

.IR m issing

658

files, which will occur when, on

659

creating an archive, a file whose name was read from the standard

660

input is not found. The default is

661

.BR "-1 m" .

662

For

663

.I afio

664

versions 2.4.3 and earlier, the default was

665

.BR "-1 a" .

666

For

667

.I afio

668

versions 2.4.4 and 2.4.5, the default was

669

.BR "-1 ''" .

670

.TP

671

.BI "-2 " maximum-file-size-to-compress

672

Do not compress any files which

673

are larger than this size when making a compressed archive

674

with the

675

.B -Z

676

option. The default value is

677

.BR "-2 200m"

678

(200 Megabytes). This maximum size cutoff lowers the risk that a major portion

679

of a large file

680

will be irrecoverable due to small media errors. If a media error occurs

681

while reading a file that

682

.I afio

683

has stored in a compressed form, then

684

.I afio

685

and

686

.I gzip

687

will not be able to restore the entire remainder of that file.

688

This is usually an acceptable risk for small files. However for very

689

large files the risk of loosing a large amount of data because

690

of this effect will usually be too big. The special case

691

.B "-2 0"

692

eliminates any maximum size cutoff.

693

.TP

694

.BI "-3 " filedescriptor-nr

695

Rewind the filedescriptor before invoking the (un)compression program

696

if using the

697

.B -Z

698

option. This

699

is useful when the

700

.B -P

701

and

702

.B -Q

703

options are used to replace the compression program

704

.I gzip

705

with some types of encryption programs in order to make or read an archive

706

with encrypted files. The rewinding is needed to interface

707

correctly with some encryption programs that read their key from an open

708

filedescriptor. If the

709

.B -P

710

program name matches 'pgp' or 'gpg', then the

711

.B -3

712

option

713

.I must

714

be used to avoid

715

.IR afio (1)

716

reporting an error. Use the special case

717

.B "-3 0"

718

to supress the error message without rewinding any file descriptor.

719

The

720

.B "-3 0"

721

option may also be needed to sucessfully read back encrypted archives

722

made with

723

.I afio

724

version 2.4.5 and older.

725

.TP

726

.B -4

727

Write archive in the `extended ASCII' format which uses 4-byte

728

inode numbers. Archives using the extended ASCII format are

729

.B not

730

compatible with any other archiver. This option should not be used

731

unless the set of files to be archived contains over 60 thousand hard

732

links and all set-internal hard links need to be preserved in the

733

archive. A complete news spool could be an example of such a set of

734

files. For such sets, the standard archive format would not

735

necessarily perserve all internal hard links (see the BUGS section).

736

.TP

737

.B -9

738

Do not round down any

739

.B -s

740

volume sizes to the nearest

741

.B -b

742

block size. See the

743

.B -s

744

option.

745

.PP

746

.SH NOTES

747

Special-case archive names:

748

.RS 3

749

.TP 3

750

.B o

751

Specify

752

.I \-

753

to read or write the standard input or output, respectively.

754

This disables multi-volume archive handling.

755

.TP

756

.B o

757

Prefix a command string to be executed with an exclamation mark

758

.RI ( ! ).

759

The command is executed once for each archive volume,

760

with its standard input or output piped to

761

.IR afio .

762

It is expected to produce a zero exit code when all is well.

763

.TP

764

.B o

765

Use

766

.I system:file

767

to access an archive in

768

.I file

769

770

.IR system .

771

This is really just a special case of pipelining.

772

It requires a 4.2BSD-style remote shell

773

.RI ( rsh (1C))

774

and a remote copy of

775

.IR afio .

776

.TP

777

.B o

778

A more elaborate case of the above is

779

.I [user@]host[%rsh][=afio]:file

780

where the optional

781

.I user@

782

component specifies the user name on the remote host, the optional

783

.I %rsh

784

specifies the (local) name of the remote shell command to use,

785

and the optional

786

.I =afio

787

specifies the name of the remote copy of the afio command.

788

.TP

789

.B o

790

Anything else specifies a local file or device.

791

An output file will be created if it does not already exist.

792

.RE

793

.PP

794

Recognizes obsolete binary

795

.IR cpio (1)

796

archives (including those from machines with reversed byte order),

797

but cannot write them.

798

.PP

799

Recovers from archive corruption by searching for a valid magic

800

number. This is rather simplistic, but, much like a disassembler,

801

almost always works.

802

.PP

803

Optimizes pathnames with respect to the current and parent

804

directories. For example,

805

.I ./src/sh/../misc/afio.c

806

becomes

807

.IR src/misc/afio.c .

808

.SH CONTROL FILES

809

.I Afio

810

archives can contain so-called control files. Unlike normal archive

811

entries, a control file in not unpacked to the filesystem. A control

812

file has a

813

.I label

814

and some

815

.IR data .

816

When

817

.I afio

818

encounters a control file in the archive it is reading, it will feed the

819

.I label

820

and

821

.I data

822

to a so-called control script. The control script is supplied by

823

the user. It can perform special actions based on the

824

.I label

825

and

826

.I data

827

it receives from

828

.IR afio .

829

.PP

830

.B Control file labels.

831

The control file mechanism can be used for many things. Examples are

832

putting archive descriptions at the beginning of the archive and

833

embedding lists of files to move before unpacking the rest or the

834

archive.

835

.PP

836

To distinguish between different uses, the

837

.I label

838

of a control file should indicate the program that made the contol

839

file and the purpose of the control file data. It should have the

840

form

841

.PP

842

.nf

843

programname.kindofdata

844

.fi

845

.PP

846

where

847

.I programname

848

is the name of the backup program that generated the control file, and

849

.I kindofdata

850

is the meaning of the control file data. Some examples are

851

.PP

852

.nf

853

tbackup.movelist tbackup.updatescript

854

blebberfiler.archivecontents

855

backup_script_of_Joe_User.archivedescription

856

.fi

857

.PP

858

The user-supplied control script should look at the label to decide

859

what to do with the control data. This way, control files with

860

unknown labels can be ignored, and afio archives maintain some degree

861

of portability between different programs that restore or index them.

862

.PP

863

Control file labels that are intended to be portable between different

864

backup programs could be defined in the future.

865

.PP

866

.B Making control files.

867

When making an archive, afio reads a stream containing the names of the

868

files (directories, ...) to put in the archive. This stream may also

869

contain `control file generators', which are lines with the following

870

format:

871

.PP

872

.nf

873

//--sourcename label

874

.fi

875

.PP

876

Here, the //-- sequence signals that a control file is to be made,

877

.I sourcename

878

is the path to a file containing the control file data, and

879

.I label

880

is the control file label. The

881

.I sourcename

882

must be a regular file or a symlink to a regular file.

883

.PP

884

A control file will show up as

885

.PP

886

.nf

887

//--CONTROL_FILE/label

888

.fi

889

.PP

890

in an archive listing, where

891

.I label

892

is the control file label.

893

.PP

894

.B Control scripts.

895

A control script is supplied to afio with the

896

.PP

897

.BI " -D " controlscript

898

.PP

899

command line option. The

900

.I controlscript

901

must be an executable program. The script is

902

run whenever

903

.I afio

904

encounters a control file while doing a

905

.B -i -t

906

907

.B -r

908

operation. Afio will supply the control file

909

.I label

910

as an argument to the script. The script should read the control file

911

.I data

912

from its standard input. If the script exits with a non-zero exit

913

status,

914

.I afio

915

will issue a warning message.

916

.PP

917

If a contol file is encountered and no

918

.B -D

919

option is given,

920

.I afio

921

will issue a warning message. To suppress the warning message and

922

ignore all control scripts,

923

.B -D

924

925

can be used.

926

.PP

927

An example of a control script is

928

.PP

929

.nf

930

#!/bin/sh

931

if [ $1 = "afio_example.headertext" ]; then

932

#the headertext control file is supposed to be packed as the first

933

#entry of the archive

934

echo Archive header:

935

cat -

936

echo Unpack this archive? y/n

937

#stdout is still connected to the tty, read the reply from stdout

938

read yn <&1

939

if [ "$yn" = n ]; then

940

#abort

941

kill $PPID

942

943

else

944

echo Ignoring unknown control file.

945

cat - >/dev/null

946

947

.fi

948

.PP

949

.I Afio

950

never compresses the control file data when storing it in an archive,

951

even when the

952

.B -Z

953

option is used. When a control file is encountered by

954

.I cpio(1)

955

or an

956

.I afio

957

with a version number below 2.4.1, the data will be unpacked to the

958

filesystem, and named

959

.I CONTROL_FILE/label

960

where

961

.I label

962

is the control file label.

963

.SH BUGS

964

There are too many options.

965

.PP

966

Restricts pathnames to 1023 characters,

967

and 255 meaningful elements (where each element is a pathname

968

component separated by a /).

969

.PP

970

Cannot archive of files larger than 2 GB,

971

even if compiled with large filesystem support.

972

(Pre-2.4.7 versions of afio did not deal with this problem gracefully,

973

see HISTORY file for details.)

974

.PP

975

Does not use the same default block size as

976

.IR tar (1).

977

.IR tar (1)

978

uses 10 KB,

979

.I afio

980

uses 5 KB by default. Some tape drives only work with a 10 KB block size,

981

in that case the

982

.I afio

983

option

984

.B \-b 10k

985

is needed to make the tape work.

986

.PP

987

There is no sequence information within multi-volume archives.

988

Input sequence errors generally masquerade as data corruption.

989

A solution would probably be mutually exclusive with

990

.IR cpio (1)

991

compatibility.

992

.PP

993

Degenerate uses of symbolic links are mangled by pathname optimization.

994

For example, assuming that "usr.src" is a symbolic link to "/usr/src",

995

the pathname "usr.src/../bin/cu" is mis-optimized into "bin/cu" (rather

996

than "/usr/bin/cu").

997

.PP

998

The

999

.I afio

1000

code for handling floppies

1001

.RB ( -F

1002

and

1003

.BR -f " and " -K

1004

options) has buggy error handling.

1005

.I afio

1006

does not allow one to retry a failed floppy write on a different floppy,

1007

and it cannot recover from a verify error.

1008

If the floppy handling code is used and write or verify errors do occur,

1009

it is best to restart

1010

.I afio

1011

completely.

1012

Making backups to floppies should really be done with a more specialised

1013

backup program that wraps

1014

.IR afio .

1015

.PP

1016

The Linux floppy drivers below kernel version 1.1.54 do not

1017

allow

1018

.I afio

1019

to find out about floppy write errors while writing. If you

1020

are running a kernel below 1.1.54,

1021

.I afio

1022

will happily fail to write to

1023

(say) a write protected disk and not report anything wrong! The only

1024

way to find out about write errors in this case is by watching the

1025

kernel messages, or by switching on the verify

1026

.RB ( -K )

1027

option.

1028

.PP

1029

The remote archive facilites (host:/file archive names) have not been

1030

exhaustively tested. These facilities have seen a lot of real-life use

1031

though. However, there may be bugs in the code for error handling and

1032

error reporting with remote archives.

1033

.PP

1034

An archive created with a command like

1035

.I "'find /usr/src/linux -print | afio -o ...'"

1036

will not contain the ownership and permissions of the

1037

.I /usr

1038

and

1039

.I /usr/src

1040

directories. If these directories are missing when restoring the archive,

1041

.I afio

1042

will recreate them with some default ownership and permissions.

1043

.PP

1044

Afio will not restore time stamps and owner/group information on symlinks.

1045

Afio will often change

1046

the time stamp on a directory after having restored it.

1047

.PP

1048

A restore using decompression will fail if the

1049

.I gzip

1050

binary used by

1051

.I afio

1052

is overwritten, by

1053

.I afio

1054

or by another program, during the restore. The restore will also fail if

1055

any shared libraries needed to start

1056

.I gzip

1057

are overwritten during the restore.

1058

.I afio

1059

should not normally be used to overwrite the system files on a running

1060

system. If it is used in this way, a flag like

1061

.I -Y /bin/gzip

1062

can often be added to prevent failure.

1063

.PP

1064

The

1065

.B -r

1066

option verifies the file contents of the files in the archive

1067

against the files on the filesystem, but does not cross-check details

1068

like permission bits on files, nor does it cross-check that archived

1069

directories or other non-file entities still exist on the filesystem.

1070

.PP

1071

There are several problems with archiving hard links.

1072

1) Due to internal limitations, files with hard links cannot be stored

1073

in compressed form, unless the

1074

.B -l

1075

1076

.B -U

1077

options are used which force each hard linked file to be stored separately.

1078

2) By default,

1079

unless the

1080

.B \-t

1081

option is used when writing an archive,

1082

.I afio

1083

will store only one copy of each file with hard links in the archive,

1084

and re-create the hard links on unpacking the archive. However, the

1085

capacity for storing hard links is limited to 64K files which have

1086

hard links. After processing 64K files with hardlinks (either

1087

pointing inside or outside the set of files to be archived),

1088

each instance of a new hard linked file will be stored separately and

1089

separate files will be created when unpacking. The limitation to 64K

1090

files with hard links is not present when the

1091

.B \-4

1092

option is used. 3) Archives which contain hard links and which were

1093

made with older (pre-2.4.4) versions of

1094

.I afio

1095

or with

1096

.I cpio

1097

can not always be correctly unpacked. This is really a problem in the

1098

archives and not in the current version of

1099

.IR afio .

1100

The risk of incorrect unpacking will be greater if the number of files

1101

or hard links in the archives is larger. Unlike pre-2.4.4 versions of

1102

.I afio

1103

and

1104

.IR cpio ,

1105

the current version contains heuristics which greatly reduce the

1106

risk of incorrect unpacking. Use of the current version of

1107

.I afio

1108

for unpacking older archives with hard links is strongly encouraged.

1109

4) In a selective restore, if the selection predicates do not select

1110

the first copy of a file with archive-internal hard links, then all

1111

subsequent copies, if selected, will not be correctly restored. 4)

1112

Unless the

1113

.B \-4

1114

option is used, the inode number fields in the archive headers for

1115

files with hard links of the archive will sometimes not contain the

1116

actual (least significant 16 bits of) the inode number of the original

1117

file.

1118

.PP

1119

Some Linux kernels no not allow one to create a hard link to a symbolic link.

1120

.I afio

1121

will try to re-create such hard links when unpacking an archive,

1122

but might fail due to kernel restrictions.

1123

.PP

1124

Due to internal limitations of

1125

.IR afio ,

1126

the use of the

1127

.B -U

1128

option forces the writing of file content with each hard linked file,

1129

rather than only once for every set of hard linked files.

1130

.PP

1131

When it is run without super-user priviliges,

1132

.I afio

1133

is not able to unpack a file into a directory for which it has no write

1134

permissions, even if it just created that directory itself. This can be a

1135

problem when trying to restore directory structures

1136

created by some source code control tools like RCS.

1137

.PP

1138

.SH "EXAMPLES"

1139

Create an archive with compressed files:

1140

.br

1141

.I "find .... | afio -o -v -Z /dev/fd0H1440"

1142

.PP

1143

Install (unpack) an archive with compressed files:

1144

.br

1145

.I "afio -i -v -Z achive"

1146

.PP

1147

Install (unpack) an archive with compressed files, protecting newer existing

1148

files:

1149

.br

1150

.I "afio -i -v -Z -n achive"

1151

.PP

1152

Create an archive with compressed files on floppy disks:

1153

.br

1154

.I "find .... | afio -o -v -s 1440k -F -Z /dev/fd0H1440"

1155

.PP

1156

Create an archive with all file contents encrypted by pgp:

1157

.br

1158

.I "export PGPPASSFD=3"

1159

.br

1160

.I "find .... | afio -ovz -Z -U -P pgp -Q -fc -Q +verbose=0 -3 3 archive 3<passphrasefile"

1161

.PP

1162

Create an archive on recordable CDs using the

1163

.I crdrecord

1164

utility to write each CD:

1165

.br

1166

.I "find .... | afio -o -b 2048 -s325000x -v '!cdrecord .... -'"

1167

.PP

1168

Extract a single named file from an archive on /dev/tape:

1169

.br

1170

.I "afio -i -v -Z -y /home/me/thedir/thefile /dev/tape"

1171

.br

1172

(If these do not exist yet,

1173

.I afio

1174

will also create the enclosing directories

1175

.I "home/me/myfiledir"

1176

under current working directory.)

1177

.PP

1178

Extract files matching a pattern from an archive on /dev/tape:

1179

.br

1180

.I afio -i -v -Z -y '/home/me/*' /dev/tape

1181

.br

1182

(If these do not exist yet,

1183

.I afio

1184

will also create the enclosing directories

1185

.I "home/me"

1186

under current working directory.)

1187

.PP

1188

.SH "SEE ALSO"

1189

cpio(1), find(1), tar(1), compress(1), gzip(1).

1190

.SH AUTHORS

1191

Mark Brukhartz

1192

.I "..!ihnp4!laidbak!mdb"

1193

.br

1194

Jeff Buhrt

1195

.I "uunet!sawmill!prslnk!buhrt"

1196

.br

1197

Dave Gymer

1198

.I dgymer@gdcarc.co.uk

1199

.br

1200

Andrew Stevens

1201

.I as@prg.oxford.ac.uk

1202

.br

1203

Koen Holtman (current maintainer)

1204

.I koen@hep.caltech.edu

1205

.br

1206

Anders Baekgaard

1207

.I ab@osiris.cpk.auc.dk

1208

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