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       afio - manipulate archives and files


       ...  | afio -o [ options ] archive  : write (create) archive
       afio -i [ options ] archive  : install (unpack) archive
       afio -t [ options ] archive  : list table-of-contents of archive
       afio -r [ options ] archive  : verify archive against filesystem
       afio -p [ options ] directory [ ... ] : copy files


       Afio  manipulates groups of files, copying them within the (collective)
       filesystem or between the filesystem and an afio archive.

       With -o, reads pathnames from the standard input and writes an archive.

       With  -t,  reads  an  archive  and  writes  a  table-of-contents to the
       standard output.

       With -i, installs the contents of an archive relative  to  the  working

       With  -p,  reads pathnames from the standard input and copies the files
       to each directory.  Cannot be combined with the -Z option.

       With -r, reads archive and verifies it against the filesystem.  This is
       useful for verifying tape archives.

       Creates  missing  directories  as  necessary, with permissions to match
       their parents.

       Removes leading slashes from pathnames, making all  paths  relative  to
       the current directory.  This is a safety feature to prevent inadvertent
       overwriting of system files when  doing  restores.   To  suppress  this
       safety  feature,  the  -A option must be used while writing an archive,
       but also  when  reading  (installing),  verifying,  and  cataloging  an
       existing archive.

       Supports  compression  while  archiving,  with  the  -Z  option.   Will
       compress individual files  in  the  archive,  not  the  entire  archive
       datastream,  which makes afio compressed archives much more robust than
       tar zc type archives.

       Supports multi-volume archives during interactive operation (i.e., when
       /dev/tty is accessible and SIGINT is not being ignored).


       afio  archives are portable between different types of UNIX systems, as
       they contain only ASCII-formatted header information.

       Except in special cases discussed below, afio will create archives with
       the  same  format  as  ASCII  cpio(1)  archives.  Therefore cpio(1) can
       usually be used to restore an afio archive in the case that afio is not
       available  on  a  system.  (With most cpio versions, to unpack an ASCII
       format archive, use cpio -c, and for GNU  cpio(1)  use  cpio  -H  odc.)
       When  unpacking  with  cpio,  any  compressed  files  inside an afio -Z
       archive are not uncompressed by cpio, but will be created on  the  file
       system as compressed files with a .z extension.

       Unfortunately,  the  ASCII  cpio  archive  format cannot represent some
       files and file  properties  that  can  be  present  in  a  modern  UNIX
       filesystem.   If afio creates an archive with such things, then it uses
       an  afio-specific  ’large  ASCII’  header  for  the  files   concerned.
       Archives with large ASCII headers cannot be unpacked completely by cpio
       or afio versions before 2.4.8.

       When creating an archive, the ‘large ASCII’ header is used by  afio  to
       cover the following situations:

          o  A file has a size larger than 2 GB

          o  The archive contains more than 64K files which have hard links

          o  A  file, directory, or special file has a UID or GID value larger
             than 65535.

       The -5 option can be used to always  preserve  cpio  compatibility,  it
       will  cause afio to fail rather than produce an incompatible archive in
       the cases above.

       Archives made using the (deprecated) -4 option are also not  compatible
       with  cpio, but they are compatible with afio versions 2.4.4 and later.


       An afio archive file has a simple format. The  archive  starts  with  a
       file  header  for the first file, followed by the contents of the first
       file (which will either be the exact  contents  byte-for-byte,  or  the
       exact  contents in some compressed format).  The data of the first file
       is immediately followed by the file header of the second file,  and  so
       on.   At  the  end, there is a special ‘end of archive’ header, usually
       followed by some padding bytes.

       A multi-volume afio archive is simply a normal archive  split  up  into
       multiple  parts.  There are no special volume-level data headers.  This
       means that that volumes can be split and merged by  external  programs,
       as  long  as the data stays in the correct order.  It also implies that
       the contents of a single file can cross volume  boundaries.   Selective
       restores of files at known volume locations can be done by feeding only
       the needed volumes to afio, provided that the -k option is used.

       The contents of hard linked files are (unless the -l  option  is  used)
       only  stored  once  in  the  archive.  The file headers for the second,
       third, and later occurence of a hard linked file  have  no  data  after
       them.   This makes selective restores of hard-liked files difficult: if
       later occurences are to be  restored  correctly,  the  first  occurence
       always needs to be selected too.


       -@ address   Send  email  to address when a volume change (tape change,
                    floppy  change)  is  needed,  and  also  when  the  entire
                    operation is complete.  Uses sendmail(1) to send the mail.

       -a           Preserve the last access times (atimes) of the files  read
                    when  making  or  verifying  an archive.  Warning: if this
                    option is used, afio will change the  last  inode  changed
                    times  (ctimes)  of these files.  Thus, this option cannot
                    be used together with an incremental  backup  scheme  that
                    relies on the ctimes being preserved.

       -b size      Read  or write size-character archive blocks.  Suffices of
                    b,  k,  m  and  g  denote  multiples  of  512,  kilobytes,
                    megabytes  and  gigabytes, respectively.  Defaults to 5120
                    for compatibility with cpio(1).  In  some  cases,  notably
                    when  using  ftape with some tape drives, -b 10k is needed
                    for compatibility.  Note that -b 10k is the default  block
                    size used by tar(1), so it is usually a good choice if the
                    tape setup is known to work with tar(1).

       -c count     Buffer count archive  blocks  between  I/O  operations.  A
                    large   count   is  recommended  for  efficient  use  with
                    streaming magnetic tape drives, in  order  to  reduce  the
                    number of tape stops and restarts.

       -d           Don’t create missing directories.

       -e bound     Pad  the  archive  to  a  multiple  of  bound  characters.
                    Recognizes the same suffices as -s.  Defaults to  1x  (the
                    -b block size) for compatibility with cpio(1).

       -f           Spawn  a  child  process to actually write to the archive;
                    provides a clumsy form of double-buffering.   Requires  -s
                    for multi-volume archive support.

       -g           Change   to   input  file  directories.  Avoids  quadratic
                    filesystem behavior with long similar pathnames.  Requires
                    all absolute pathnames, including those for the -o archive
                    and the -p directories.

       -h           Follow symbolic links, treating them as ordinary files and

       -j           Don’t  generate  sparse  filesystem  blocks  on  restoring
                    files.  By default, afio creates sparse filesystem  blocks
                    (with lseek(2)) when possible when restoring files from an
                    archive,  but  not  if  these  files  were  stored  in   a
                    compressed  form.    Unless  stored  in a compressed form,
                    sparse files are not archived efficiently: they will  take
                    space  equal  to  the  full file length.  (The sparse file
                    handling in afio does not make  much  sense  except  in  a
                    historical way.)

       -k           Rather  than  complaining about unrecognizable input, skip
                    unreadable  data  (or  partial  file  contents)   at   the
                    beginning  of  the archive file being read, and search for
                    the next valid archive header.  This option is  needed  to
                    deal  with  certain  types  of backup media damage.  It is
                    also useful  to  support  quick  selective  restores  from
                    multi-volume  archives,  or from searchable block devices,
                    if the volume or location of the file to  be  restored  is
                    known  in advance (see the -B option).  If, for example, a
                    selective restore is done with  the  fourth  volume  of  a
                    multi-volume  afio archive, then the -k option needs to be
                    used, else afio will complain about the input not being  a
                    well-formed archive.

       -l           With -o, write file contents with each hard link.

                    With -t, report hard links.

                    With -p, attempt to link files rather than copying them.

       -m           Mark  output files with a common current timestamp (rather
                    than with input file modification times).

       -n           Protect newer existing files (comparing file  modification

       -s size      Restrict  each  portion  of a multi-volume archive to size
                    characters. This option recognizes the same size  suffices
                    as  -b.   Also,  the suffix x denotes a multiple of the -b
                    block size (and must follow any -b  specification).   size
                    can  be a single size or a  comma-seperated list of sizes,
                    for example ’2m,5m,8m’, to specify different sizes for the
                    subsequent volumes.  If there are more volumes than sizes,
                    the last specified size is used for all remaining volumes.
                    This  option is useful with finite-length devices which do
                    not return short counts at end of media (sigh); output  to
                    magnetic  tape  typically falls into this category.   When
                    an archive is being read or written, using -s causes  afio
                    to  prompt  for  the  next  volume if the specified volume
                    length is reached.  The -s option will also cause afio  to
                    prompt  if  there  is  a  premature  EOF while reading the
                    input.  The special case -s 0 will activate this prompting
                    for  the  next  volume  on premature EOF without setting a
                    volume length.  When writing an archive, afio will  prompt
                    for  the  next  volume  on end-of-media, even without -s 0
                    being supplied, if the device is capable of reporting end-
                    of-media.   If the volume size specified is not a multiple
                    of the block size set with the  -b  option,  then  afio(1)
                    will  silently  round  down the volume size to the nearest
                    multiple of the block size.  This  rounding  down  can  be
                    suppressed  using  the  -9  option: if -9 is used, afio(1)
                    will write a small block of  data,  smaller  than  the  -b
                    size,  at  the  end of the volume to completely fill it to
                    the  specified size.  Some devices are not able to  handle
                    such small block writes.

       -u           Report files with unseen links.

       -v           Verbose.   Report   pathnames  (to  stderr)  as  they  are
                    processed. When used with -t, gives an ls -l style  report
                    (including link information) to stdout instead.  When used
                    twice (-vv) with -o, gives an ls -l style report to stdout
                    while  writing  the archive. (But this use of -vv will not
                    work if the archive is also being written to stdout.)

       -w filename  Treats each line in filename as an -y pattern, see -y.

       -x           Retain file ownership and setuid/setgid permissions.  This
                    is  the  default  for  the  super-user;  he  may use -X to
                    override it.

       -y pattern   Restrict processing  of  files  to  names  matching  shell
                    wildcard  pattern  pattern.   Use  this flag once for each
                    pattern to be recognized.  With the possible exception  of
                    the presence of a leading slash, the complete file name as
                    appearing in the archive table-of-contents must match  the
                    pattern, for example the file name ’etc/passwd’ is matched
                    by the pattern ’*passwd’ but NOT by the pattern  ’passwd’.
                    See  ‘man  7  glob’ for more information on shell wildcard
                    pattern matching.  The only difference with shell wildcard
                    pattern  matching  is that in afio the wildcards will also
                    match ’/’ characters  in  file  names.   For  example  the
                    pattern    ’/usr/src/*’   will   match   the   file   name
                    ’/usr/src/linux/Makefile’,  and  any   other   file   name
                    starting  with  ’/usr/src’. Unless the -S option is given,
                    any leading slash  in  the  pattern  or  the  filename  is
                    ignored   when  matching,  e.g.   /etc/passwd  will  match
                    etc/passwd.  Use -Y to supply patterns which are not to be
                    processed.   -Y  overrides  -y if a filename matches both.
                    See also -w and -W.  Note: if afio  was  compiled  without
                    using  the  GNU  fnmatch  library,  then  the  full  shell
                    wildcard pattern  syntax  cannot  be  used,  and  matching
                    support  is  limited  to patterns which are a full literal
                    file name and patterns which end in ’*’.

       -z           Print  execution  statistics.  This  is  meant  for  human
                    consumption;   use   by   other   programs  is  officially

       -A           Do not turn absolute paths into relative  paths.  That  is
                    don’t remove the leading slash.  Applies to the path names
                    written in an archive, but also to the path names read out
                    of   an   archive   during  read  (install),  verify,  and
                    cataloging operations.

       -B           If the -v option is used, prints the byte  offset  of  the
                    start of each file in the archive.  If your tape drive can
                    start reading at any position in an archive, the output of
                    -B can be useful for doing quick selective restores.

       -D controlscript
                    Set  the  control  script  name  to controlscript, see the
                    section on control files below.

       -E [+]filename | -E CS | -E CI
                    While creating an archive with compressed files using  the
                    -Z  option,  disable  (attempts  at) compression for files
                    with particular extensions.  This option can  be  used  to
                    speed up the creation of the archive, by making afio avoid
                    trying to use gzip on files that contain  compressed  data
                    already.   By  default, if no specific -E option is given,
                    all files with the extensions .Z .z  .gz  .bz2  .tgz  .arc
                    .zip  .rar  .lzh  .lha  .uc2 .tpz .taz .tgz .rpm .zoo .deb
                    .gif .jpeg .jpg .tif .tiff .png .pdf .arj .avi  .bgb  .cab
                    .cpn .hqx .jar .mp3 .mpg .mpq .pic .pkz .psn .sit .ogg and
                    .smk will not be compressed.  Also by  default,  the  file
                    extension  matching  is  case-insensitive (to do the right
                    thing with respect  to  MS-DOS  based  filesystems).   The
                    -E filename  form  of this option will replace the default
                    list of file extensions by reading  a  new  list  of  file
                    extensions,   separated   by  whitespace,  from  filename.
                    filename may  contain  comments  preceded  by  a  #.   The
                    extensions  in  filename  should  usually all start with a
                    dot, but they do not need to start with a dot, for example
                    the  extension ’tz’ will match the file name ’hertz’.  The
                    -E +filename form (with a + sign in front of filename) can
                    be  used to specify extensions in addition to the built-in
                    default list, instead of replacing the whole default list.
                    To make extension matching case-sensitive, add the special
                    option form -E CS to the command line.   The  form  -E  CI
                    invokes  the  (default)  case-insensitive comparison.  See
                    also the -6 option, which  offers  an  additional  way  to
                    suppress compression.

       -F           This  is  a  floppy  disk,  -s is required.  Causes floppy
                    writing in O_SYNC mode under Linux.  With  kernel  version
                    1.1.54  and  above, this allows afio to detect some floppy
                    errors while writing.  Uses shared memory if  compiled  in
                    otherwise  mallocs  as  needed  (a 3b1 will not be able to
                    malloc the needed memory w/o shared memory), afio  assumes
                    either  way you can malloc/shmalloc a chunck of memory the
                    size of one disk. Examples: 795k: 3.5" (720k drive),  316k
                    (360k drive)
                    At the end of each disk this message occurs:
                     Ready for disk [#] on [output]
                     (remove the disk when the light goes out)
                     Type "go" (or "GO") when ready to proceed
                     (or "quit" to abort):

       -G factor    Specifies  the gzip(1) compression speed factor, used when
                    compressing files with the -Z option.   Factor  1  is  the
                    fastest  with  least  compression,  9 is slowest with best
                    compression.  The  default  value  is  6.   See  also  the
                    gzip(1) manual page.  If you have a slow machine or a fast
                    backup medium, you may want to specify  a  low  value  for
                    factor to speed up the backup.  On large (>200k) files, -G
                    1 typically zips twice  as  fast  as  -G  6,  while  still
                    achieving a better result than compress(1).  The zip speed
                    for small files is mainly  determined  by  the  invocation
                    time of gzip (1), see the -T option.

       -H promptscript
                    Specify  a  script  to  run,  in stead of using the normal
                    prompt, before advancing to the next achive  volume.   The
                    script  will  be  run with the next volume number, archive
                    specification, and the reason for  changing  to  the  next
                    volume as arguments.  The script should exit with 0 for OK
                    and 1 for abort, other exit codes will be treated as fatal
                    errors.    afio   executes   the   script  by  taking  the
                    promptscript string, appending  the  arguments,  and  then
                    calling  the  shell to execute the resulting command line.
                    This means that a general-purpose  prompt  script  can  be
                    supplied  with  additional arguments, via the afio command
                    line,   by   using   a   -H   option   value    like    -H
                    "generic_promptscript  additional_arg_1 additional_arg_2".

       -J           Try to continue after a media write  error  when  doing  a
                    backup (normal behavior is to abort with a fatal error).

       -K           Verify  the  output  against what is in the memory copy of
                    the disk (-F required).  If the writing or verifying fails
                    the following menu pops up
                        [Writing/Verify] of disk [disk #] has FAILED!
                         Enter 1 to RETRY this disk
                         Enter 2 to REFORMAT this disk before a RETRY

                         Enter quit to ABORT this backup
                    Currently,  afio  will  not process the answers 1 and 2 in
                    the right way.  The menu above is only useful in  that  it
                    signifies that something is wrong.

       -L Log_file_path
                    Specify  the  name of the file to log errors and the final
                    totals to.

       -M size      Specifies the maximum amount of  memory  to  use  for  the
                    temporary storage of compression results when using the -Z
                    option. The default  is  -M  2m  (2  megabytes).   If  the
                    compressed  version  of  a file is larger than this (or if
                    afio runs out of virtual memory), gzip(1) is run twice  of
                    the  file,  the  first time to determine the length of the
                    result, the second time to get the compressed data itself.

       -P progname  Use  the  program progname instead of the standard gzip(1)
                    for compression and decompression with the -Z option.  For
                    example,  use the options -Z -P bzip2 to write and install
                    archives using bzip2(1) compression.  If progname does not
                    have  command  line options (-c, -d, and -<number>) in the
                    style of gzip(1) then the -Q option can be used to  supply
                    the right options.  See also the -Q, -U and -3 options.

       -Q opt       Pass  the  option  opt to the compression or decompression
                    program used with the  -Z  option.  For  passing  multiple
                    options, use -Q multiple times.  If no -Q flag is present,
                    the standard options are passed.  The standard options are
                    -c -6 when the program is called for compression and -c -d
                    when the program is called  for  decompression.   Use  the
                    special  case  -Q "" if no options at all are to be passed
                    to the program.

       -R Disk format command string
                    This is the command that  is  run  when  you  enter  2  to
                    reformat  the  disk  after  a  failed verify.  The default
                    (fdformat  /dev/fd0H1440)  can  be  changed  to  a   given
                    system’s  default  by  editing the Makefile.  You are also
                    prompted  for  formatting  whenever  a  disk   change   is

       -S           Do  not  ignore a leading slash in the pattern or the file
                    name when matching -y and -Y patterns. See also -A.

       -T threshold Only compress a file when  using  the  -Z  option  if  its
                    length is at least threshold.  The default is -T 0k.  This
                    is useful if you have a slow  machine  or  a  fast  backup
                    medium.   Specifying  -T 3k typically halves the number of
                    invocations of gzip(1), saving some 30% computation  time,
                    while  creating  an  archive  that is only 5% longer.  The
                    combination -T 8k -G 1  typically  saves  70%  computation
                    time   and   gives   a  20%  size  increase.   The  latter
                    combination may be a good alternative to not using  -Z  at
                    all.   These  figures of course depend heavily on the kind
                    of files in the archive and  the  processor  -  i/o  speed
                    ratio on your machine.  See also the -2 option.

       -U           If  used with the -Z option, forces compressed versions to
                    be stored of all files, even if  the  compressed  versions
                    are  bigger  than  the original versions, and disregarding
                    any (default) values of the -T and -2  options.   This  is
                    useful  when the -P and -Q options are used to replace the
                    compression program gzip with  an  encryption  program  in
                    order  to  make  an  archive with encrypted files.  Due to
                    internal limitations of afio, use of this flag forces  the
                    writing of file content with each hard linked file, rather
                    than only  once  for  every  set  of  hard  linked  files.
                    WARNING:  use of the -U option will also cause compression
                    (or whatever operation the -P option indicates)  on  files
                    larger  than 2 GB, if these are present in the input.  Not
                    all compression programs  might  handle  such  huge  files
                    correctly  (recent  Linux versions of gzip, bzip2, and gpg
                    have all been tested and seem to work OK). If  your  setup
                    is obscure, some testing might be warranted.

       -W filename  Treats each line in filename as an -Y pattern, see -Y.

       -Y pattern   Do  not  process  files  whose  names match shell wildcard
                    pattern pattern.  See also -y and -W.

       -Z           Compress the files that go into the archive when  creating
                    an  archive,  or  uncompress them again when installing an
                    archive.  afio -Z will compress each file in  the  archive
                    individually,    while   keeping   the   archive   headers
                    uncompressed.  Compared to tar zc style archives, afio  -Z
                    archives  are  therefore  much more fault-tolerant against
                    read errors  on  the  backup  medium.   When  creating  an
                    archive  with  the  -Z  option, afio will run gzip on each
                    file encountered, and, if the result is smaller  than  the
                    original,  store  the  compressed  version  of  the  file.
                    Requires gzip(1) to be in your path.  Mainly to  speed  up
                    afio operation, compression is not attempted on a file if:
                    1) the file is very small (see the -T option), 2) the file
                    is  very  large  (see  the  -2  option), 3) the file has a
                    certain extension, so it probably contains compressed data
                    already  (see the -E option), 4) the file pathname matches
                    a certain pattern, as set by the -6 option,  5)  the  file
                    has  hard  links  (this  due  to an internal limitation of
                    afio, but this limitation does not apply if the -l  option
                    is  also used).  Regardless of the above, if the -U option
                    is used then the compression program is  always  run,  and
                    the  compressed  result is always stored.  When installing
                    an archive with compressed files, the -Z option  needs  to
                    be used in order to make afio automatically uncompress the
                    files that it compressed earlier.  The -P  option  can  be
                    used  to  do  the (un)compression with programs other than
                    gzip, see the -P (and -Q and -3) options in  this  manpage
                    for  details.   See  also the -G option which provides yet
                    another way to tune the compression process.

       -0           Assume input  filenames  to  be  terminated  with  a  ’\0’
                    instead of a ’\n’. When used with find ... -print0, can be
                    used to ensure that any filename can be handled,  even  if
                    it contains a newline. When used with option -t the output
                    filenames will be separated by nullbytes. If a patternfile
                    is  used  with  -w  or  -W  it  has  also  to  use ’\0’ as

       -1 warnings-to-ignore
                    Control if afio(1) should exit with a nonzero  code  after
                    printing  certain warning messages, and if certain warning
                    messages  should  be  printed  at  all.   This  option  is
                    sometimes useful when calling afio(1) from inside a backup
                    script or program.  afio(1) will exit with a nonzero  code
                    on  encountering various ’hard’ errors, and also (with the
                    default value of  the  -1  option)  when  it  has  printed
                    certain  warning  messages during execution.  warnings-to-
                    ignore is a list of letters which determines the  behavior
                    related  to  warning messages.  The default value for this
                    option is -1 mc.  For afio versions 2.4.3 and earlier, the
                    default  was -1 a.  For afio versions 2.4.4 and 2.4.5, the
                    default was -1 ’’.  The defined warnings-to-ignore letters
                    are  as  follows.   a  is  for  for  ignoring all possible
                    warnings on exit: if this letter is used, the printing  of
                    a warning message will never cause a nonzero exit code.  m
                    is for ignoring in the exit code any warning about missing
                    files, which will be printed when, on creating an archive,
                    a file whose name was read from the standard input is  not
                    found.   c  is  for  ignoring in the exit code the warning
                    that the archive being  created  will  not  be  not  fully
                    compatible  with  cpio or afio versions 2.4.7 or lower.  C
                    is the same as c, but in addition the warning message will
                    not  even be printed.  M will suppress the printing of all
                    warning  messages  asssociated  with  Multivolume  archive
                    handling,   messages   like  "Output  limit  reached"  and
                    "Continuing".  n is  for  ignoring  in  the  exit  code  a
                    particular  class  of  no-such-file  warnings:  it ignores
                    these warnings when they happen after the file has already
                    been  succesfully  opened.  This unusual warning situation
                    can  occur  when  archiving   files   on   Windows   smbfs
                    filesystems  -- due to a Windows problem, smbfs files with
                    non-ASCII characters  in  their  names  can  sometimes  be
                    opened  but  not  read.  When the -Z option is used, the n
                    letter function is (currently) only implemented for  files
                    with  sizes smaller than indicated by the -T option, so in
                    that case the -T option is also needed for this letter  to
                    have any effect.

       -2 maximum-file-size-to-compress
                    Do  not compress any files which are larger than this size
                    when making a compressed archive with the -Z  option.  The
                    default  value  is  -2  200m (200 Megabytes). This maximum
                    size cutoff lowers the risk that  a  major  portion  of  a
                    large  file  will  be  irrecoverable  due  to  small media
                    errors.   If a media error occurs  while  reading  a  file
                    that  afio  has stored in a compressed form, then afio and
                    gzip will not be able to restore the entire  remainder  of
                    that  file.   This is usually an acceptable risk for small
                    files. However for very large files the risk of loosing  a
                    large  amount  of data because of this effect will usually
                    be too big.  The special case -2 0 eliminates any  maximum
                    size cutoff.

       -3 filedescriptor-nr
                    Rewind    the    filedescriptor    before   invoking   the
                    (un)compression program if using the -Z  option.  This  is
                    useful  when the -P and -Q options are used to replace the
                    compression program gzip with  some  types  of  encryption
                    programs  in  order  to  make  or  read  an  archive  with
                    encrypted files.  The rewinding  is  needed  to  interface
                    correctly  with  some  encryption programs that read their
                    key from an open filedescriptor.  If the -P  program  name
                    matches ’pgp’ or ’gpg’, then the -3 option must be used to
                    avoid afio(1) reporting an error.  Use the special case -3
                    0  to supress the error message without rewinding any file
                    descriptor.  The  -3  0  option  may  also  be  needed  to
                    sucessfully  read  back  encrypted archives made with afio
                    version 2.4.5 and older.

       -4           (Deprecated, the intended effect of  this  option  is  now
                    achieved  by default as long as the -5 option is not used.
                    This option could still be useful for  compatibility  with
                    machines running an older version of afio.)  Write archive
                    with the ‘extended ASCII’ format headers which use  4-byte
                    inode  numbers.   Archives using the extended ASCII format
                    headers are not compatible with any other archiver.   This
                    option was useful for reliably creating and restoring sets
                    of files with many internal hard links, for example a news

       -5           Refuse  to  create  an  archive  that is incompatible with
                    cpio(1).  If this option is used, afio  will  never  write
                    any  ‘large ASCII’ file headers that are incompatible with
                    cpio(1), but fail with an error  code  instead.   See  the
                    ARCHIVE  PORTABILITY section above for more information on
                    the use of ‘large ASCII’ file headers.

       -6  filename While creating an archive with compressed files using  the
                    -Z  option,  disable  (attempts  at) compression for files
                    that match particular shell patterns.  This option can  be
                    used  to  speed  up the creation of the archive, by making
                    afio avoid trying  to  use  gzip  on  files  that  contain
                    compressed  data  already.   Reads shell wildcard patterns
                    from filename,  treating  each  line  in  the  file  as  a
                    pattern.   Files  whose names match these patterns are not
                    to be  compressed  when  using  the  -Z  option.   Pattern
                    matching  is done in exactly the same way as described for
                    the -y option.  See also  the  -E  option:  the  (default)
                    settings   of   the   -E   option  will  further  restrict
                    compression attempts.  The -E option controls  compression
                    attempts based on file extensions; the -6 option is mainly
                    intended as a method for excluding all  files  in  certain
                    subdirectory trees from compression.

       -7           Disable globbing so that it is possible to use -W or -w to
                    specify a list of exact filenames to exclude or extract.

       -9           Do not round down any -s volume sizes to  the  nearest  -b
                    block size.  See the -s option.


       Special-case archive names:

          o  Specify  -  to  read  or  write  the  standard  input  or output,
             respectively.  This disables multi-volume archive handling.

          o  Prefix a command string to be executed with an  exclamation  mark
             (!).   The command is executed once for each archive volume, with
             its standard input or output piped to afio.  It  is  expected  to
             produce a zero exit code when all is well.

          o  Use  system:file to access an archive in file on system.  This is
             really just a special case of pipelining.  It requires a  4.2BSD-
             style remote shell (rsh(1C)) and a remote copy of afio.

          o  A     more     elaborate     case     of     the     above     is
             [user@]host[%rsh][=afio]:file where the optional user@  component
             specifies  the  user  name  on the remote host, the optional %rsh
             specifies the (local) name of the remote shell  command  to  use,
             and  the  optional =afio specifies the name of the remote copy of
             the afio command.

          o  Anything else specifies a local file or device.  An  output  file
             will be created if it does not already exist.

       Recognizes  obsolete  binary  cpio(1)  archives  (including  those from
       machines with reversed byte order), but cannot write them.

       Recovers from archive corruption by searching for a valid magic number.
       This is rather simplistic, but, much like a disassembler, almost always

       Optimizes pathnames with respect to the current and parent directories.
       For example, ./src/sh/../misc/afio.c becomes src/misc/afio.c.


       Afio  archives  can  contain  so-called  control  files.  Unlike normal
       archive entries, a control file in not unpacked to the  filesystem.   A
       control file has a label and some data.  When afio encounters a control
       file in the archive it is reading, it will feed the label and data to a
       so-called  control script.  The control script is supplied by the user.
       It can perform special actions based on the label and data it  receives
       from afio.

       Control  file  labels.  The control file mechanism can be used for many
       things.  Examples are putting archive descriptions at the beginning  of
       the  archive  and embedding lists of files to move before unpacking the
       rest or the archive.

       To distinguish between different uses, the  label  of  a  control  file
       should  indicate  the program that made the contol file and the purpose
       of the control file data.  It should have the form


       where programname is the name of the backup program that generated  the
       control  file,  and kindofdata is the meaning of the control file data.
       Some examples are

          tbackup.movelist  tbackup.updatescript

       The user-supplied control script should look at  the  label  to  decide
       what to do with the control data.  This way, control files with unknown
       labels can be ignored,  and  afio  archives  maintain  some  degree  of
       portability between different programs that restore or index them.

       Control  file labels that are intended to be portable between different
       backup programs could be defined in the future.

       Making control files.  When making an  archive,  afio  reads  a  stream
       containing  the  names  of  the  files (directories, ...) to put in the
       archive.  This stream may also contain ‘control file generators’, which
       are lines with the following format:

           //--sourcename label

       Here,  the  //--  sequence  signals  that a control file is to be made,
       sourcename is the path to a file containing the control file data,  and
       label is the control file label.  The sourcename must be a regular file
       or a symlink to a regular file.

       A control file will show up as


       in an archive listing, where label is the control file label.

       Control scripts.  A control script is supplied to afio with the

         -D controlscript

       command line option.  The controlscript must be an executable  program.
       The script is run whenever afio encounters a control file while doing a
       -i -t or -r operation.  Afio will supply the control file label  as  an
       argument  to  the script.  The script should read the control file data
       from its standard input.  If the script  exits  with  a  non-zero  exit
       status, afio will issue a warning message.

       If  a  contol  file is encountered and no -D option is given, afio will
       issue a warning message.  To suppress the warning  message  and  ignore
       all control scripts, -D "" can be used.

       An example of a control script is

         if [ $1 = "afio_example.headertext" ]; then
           #the headertext control file is supposed to be packed as the first
           #entry of the archive
           echo Archive header:
           cat -
           echo Unpack this archive? y/n
           #stdout is still connected to the tty, read the reply from stdout
           read yn <&1
           if [ "$yn" = n ]; then
             kill $PPID
           echo Ignoring unknown control file.
           cat - >/dev/null

       Afio  never  compresses  the  control  file  data when storing it in an
       archive, even when the -Z option is  used.   When  a  control  file  is
       encountered  by  cpio(1)  or an afio with a version number below 2.4.1,
       the  data   will   be   unpacked   to   the   filesystem,   and   named
       CONTROL_FILE/label where label is the control file label.


       There are too many options.

       Restricts  pathnames  to  1023  characters, and 255 meaningful elements
       (where each element is a pathname component separated by a /).

       Does not use the same default block size as tar(1).  tar(1) uses 10 KB,
       afio  uses  5  KB  by  default. Some tape drives only work with a 10 KB
       block size, in that case the afio option -b 10k is needed to  make  the
       tape work.

       There  is  no sequence information within multi-volume archives.  Input
       sequence errors generally masquerade as data  corruption.   A  solution
       would probably be mutually exclusive with cpio(1) compatibility.

       Degenerate uses of symbolic links are mangled by pathname optimization.
       For example, assuming that "usr.src" is a symbolic link to  "/usr/src",
       the pathname "usr.src/../bin/cu" is mis-optimized into "bin/cu" (rather
       than "/usr/bin/cu").

       The afio code for handling floppies (-F and  -f  and  -K  options)  has
       buggy  error  handling.   afio  does  not  allow  one to retry a failed
       floppy write on a different floppy, and it cannot recover from a verify
       error.   If the floppy handling code is used and write or verify errors
       do occur, it is best to restart afio  completely.   Making  backups  to
       floppies  should  really be done with a more specialised backup program
       that wraps afio.

       The Linux floppy drivers below kernel version 1.1.54 do not allow  afio
       to  find  out  about  floppy  write  errors  while writing.  If you are
       running a kernel below 1.1.54, afio will happily fail to write to (say)
       a  write protected disk and not report anything wrong!  The only way to
       find out about write errors in this case  is  by  watching  the  kernel
       messages, or by switching on the verify (-K) option.

       The  remote  archive facilites (host:/file archive names) have not been
       exhaustively tested. These facilities have seen a lot of real-life  use
       though.   However, there may be bugs in the code for error handling and
       error reporting with remote archives.

       An archive created with a command like find  /usr/src/linux  -print  |
       afio  -o  ...   will  not contain the ownership and permissions of the
       /usr and /usr/src directories. If these directories  are  missing  when
       restoring  the  archive,  afio  will  recreate  them  with some default
       ownership and permissions.

       Afio can not restore time  stamps  on  symlinks.   Also,  on  operating
       systems  without  an  lchown(2)  system  call,  afio  can  not  restore
       owner/group information on symlinks. (Linux  has  lchown  since  kernel
       version 2.1.86.)

       Afio  tries  to  restore modification time stamps of directories in the
       archive  correctly.   However,  if  it  exits  prematurely,  then   the
       modification times will not be restored correctly.

       A restore using decompression will fail if the gzip binary used by afio
       is overwritten, by afio or by another program, during the restore.  The
       restore will also fail if any shared libraries needed to start gzip are
       overwritten during the restore.  afio should not normally  be  used  to
       overwrite  the system files on a running system.  If it is used in this
       way, a flag like -Y /bin/gzip can often be added to prevent failure.

       The -r option verifies the file contents of the files  in  the  archive
       against  the  files on the filesystem, but does not cross-check details
       like permission bits on files, nor does it  cross-check  that  archived
       directories or other non-file entities still exist on the filesystem.

       There  are  several  problems  with  archiving  hard  links.  1) Due to
       internal limitations,  files  with  hard  links  cannot  be  stored  in
       compressed  form, unless the -l or -U options are used which force each
       hard linked file to be stored separately.  2)  Archives  which  contain
       hard  links and which were made with older (pre-2.4.8) versions of afio
       or with cpio can not always be correctly unpacked.  This  is  really  a
       problem  in  the  archives and not in the current version of afio.  The
       risk of incorrect unpacking will be greater if the number of  files  or
       hard  links  in  the archives is larger.  3) In a selective restore, if
       the selection predicates do not select the first copy of  a  file  with
       archive-internal  hard  links, then all subsequent copies, if selected,
       will not be correctly restored.  4) Unless the -4 option is  used,  the
       inode number fields in the archive headers for files with hard links of
       the archive will sometimes not contain the actual (least significant 16
       bits of) the inode number of the original file.

       Some Linux kernels no not allow one to create a hard link to a symbolic
       link.  afio will try to re-create such hard  links  when  unpacking  an
       archive, but might fail due to kernel restrictions.

       Due  to  internal  limitations of afio, the use of the -U option forces
       the writing of file content with each hard  linked  file,  rather  than
       only once for every set of hard linked files.

       When  it  is  run  without  super-user  priviliges, afio is not able to
       unpack a file into a directory for which it has no  write  permissions,
       even  if  it just created that directory itself.  This can be a problem
       when trying to restore directory structures created by some source code
       control tools like RCS.

       When  block or character device files are packed into an archive on one
       operating system (e.g. Linux) and unpacked on another operating system,
       which  uses  different sizes for the major and minor device number data
       types (e.g. Solaris), the major and minor numbers of the  device  files
       will not be restored correctly.  This can be a problem if the operating
       systems share a cross-mounted  filesystem.   A  workaround  is  to  use
       tar(1) for the device files.


       Create an archive with compressed files:
       find .... | afio -o -v -Z /dev/fd0H1440

       Install (unpack) an archive with compressed files:
       afio -i -v -Z achive

       Install  (unpack)  an  archive  with compressed files, protecting newer
       existing files:
       afio -i -v -Z -n achive

       Create an archive with compressed files on floppy disks:
       find .... | afio -o -v -s 1440k -F -Z /dev/fd0H1440

       Create an archive with all file contents encrypted by pgp:
       export PGPPASSFD=3
       find .... | afio -ovz -Z -U -P pgp -Q -fc -Q +verbose=0  -3  3  archive

       Create an archive on recordable CDs using the cdrecord utility to write
       each CD:
       find .... | afio -o -b 2048 -s325000x -v !cdrecord .... -

       Extract a single named file from an archive on /dev/tape:
       afio -i -v -Z -y /home/me/thedir/thefile /dev/tape
       (If these do not  exist  yet,  afio  will  also  create  the  enclosing
       directories home/me/myfiledir under current working directory.)

       Extract files matching a pattern from an archive on /dev/tape:
       afio -i -v -Z -y /home/me/* /dev/tape
       (If  these  do  not  exist  yet,  afio  will  also create the enclosing
       directories home/me under current working directory.)

       If your filesystem cannot handle files larger than 2GB, but you want to
       make an archive on that filesystem that is larger than 2GB, you use the
       following trick to split the archive into multiple files of each 1 GB:
       find /home | afio -o ... - | split -b1024m - archive.
       the files will be called archive.aa, archive.ab, etc.  You can  restore
       the whole archive using:
       cat archive.* | afio -i ... -
       The  wildcard expansion by the shell will ensure that cat will read the
       parts in the right (alphabetic) order.


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


       There  is  no  official  web  site  for  afio.   However,  the  current
       maintainer  does  post  information  on  alpha,  beta,  and  production
       releases at
       Production  releases  are  announced  on   the   comp.os.linux.announce
       The  current  maintainer  also  tries  to  make  sure  that  the latest
       production release is at the FTP site /pub/Linux/system/backup
       (This FTP  information  is  correct  until  they  rename  the  site  or
       directories again.)
       The Debian project maintains a binary distribution package of afio, see
       Bug reporting on the Debian package can be done to the Debian  project,
       bugs  with  a  scope  beyond Debian will usually also reach the current
       afio maintainer mentioned below.
       For general bug reporting, patches, suggestions and  status  inquiries,
       please  e-mail the current afio maintainer.  Though the maintenance and
       distribution effort of  afio  is  Linux-centered,  correspondence  with
       respect  to the use of afio on other operating systems is also welcome.
       When mailing the maintainer, please use the word  ‘afio’  somewhere  in
       the  subject  line,  this  lowers  the  chance  that your mail will get
       accidentally deleted. The current maintainer e-mail address is:
       (alternative e-mail if that does not work:


       Mark Brukhartz ..!ihnp4!laidbak!mdb
       Jeff Buhrt uunet!sawmill!prslnk!buhrt
       Dave Gymer
       Andrew Stevens
       Koen Holtman (current maintainer)
       Anders Baekgaard
       Too many other people to list  here  have  contributed  code,  patches,
       ideas,  and  bug  reports.   Many of these are mentioned in the HISTORY
       file that is included with the sources.