Ubuntu Manpage: grep-dctrl, grep-status, grep-available, grep-aptavail, grep-debtags

NAME

       grep-dctrl, grep-status, grep-available, grep-aptavail, grep-debtags - grep Debian control
       files

SYNOPSIS

       command --copying|-C | --help|-h | --version|-V

       command [options] filter [ file... ]

       where command  is  one  of  grep-dctrl,  grep-status,  grep-available,  grep-aptavail  and
       grep-debtags.

DESCRIPTION

       The grep-dctrl program can answer such questions as What is the Debian package foo?, Which
       version of the Debian package bar is now current?, Which Debian  packages  does  John  Doe
       maintain?,  Which Debian packages are somehow related to the Scheme programming language?,
       and with some help, Who maintain the essential packages  of  a  Debian  system?,  given  a
       useful input file.

       The  programs  grep-available,  grep-status, grep-aptavail and grep-debtags are aliases of
       (actually, symbolic links to) grep-dctrl.  These aliases use as their  default  input  the
       dpkg(1)  available  and  status  files,  the  apt-cache  dumpavail  output and the debtags
       dumpavail output, respectively.

       grep-dctrl is a specialised grep program that is meant for processing any file  which  has
       the  general  format  of a Debian package control file, as described in the Debian Policy.
       These include the dpkg available file, the dpkg status file, and the Packages files  on  a
       distribution medium (such as a Debian CD-ROM or an FTP site carrying Debian).

       You  must  give a filter expression on the command line.  The filter defines which kind of
       paragraphs (aka package records) are output.  A simple filter is a  search  pattern  along
       with any options that modify it.  Possible modifiers are --eregex, --field, --ignore-case,
       --regex and --exact-match, along with their single-letter equivalents.   By  default,  the
       search  is  a  case-sensitive  fixed  substring  match  on each paragraph (in other words,
       package record) in the input.  With suitable modifiers, this can be  changed:  the  search
       can  be  case-insensitive  and  the  pattern  can  be  seen  as  an extended POSIX regular
       expression.

       Filters can be combined to form more complex filters using the connectives --and, --or and
       --not.   Parentheses  (which  usually  need  to  be escaped for the shell) can be used for
       grouping.

       By default, the full matching paragraphs are printed  on  the  standard  output;  specific
       fields can be selected for output with the -s option.

       After  the  filter  expression comes zero or more file names.  The file name - is taken to
       mean the standard input stream.  The files are searched in order but separately; they  are
       not  concatenated  together.   In other words, the end of a file always implies the end of
       the current paragraph.

       If no file names are specified, the program name is used to identify a default input file.
       The  program  names are matched with the base form of the name of the current program (the
       0'th command line argument, if you will).

OPTIONS

Specifying the search pattern
--pattern=pattern
Specify a pattern to be searched. This switch is not generally needed, as the
pattern can be given by itself. However, patterns that start with a dash (-) must
be given using this switch, so that they wouldn't be mistaken for switches.

Modifiers of simple filters
-F field,field, ... | --field=field,field, ...
Restrict pattern matching to the fields given. Multiple field names in one -F
option and multiple -F options in one simple filter are allowed. The search named
by the filter will be performed among all the fields named, and as soon as any one
of them matches, the whole simple filter is considered matching.

A field specification can contain a colon (:). In such a case, the part up to the
colon is taken as the name of the field to be searched in, and the part after the
colon is taken as the name of the field whose content is to be used if the field to
search in is empty.

-P Shorthand for -FPackage.

-S Shorthand for -FSource:Package.

-e, --eregex
Regard the pattern of the current simple filter as an extended POSIX regular
expression

-r, --regex
Regard the pattern of the current simple filter as a standard POSIX regular
expression.

-i, --ignore-case
Ignore case when looking for a match in the current simple filter.

-X, --exact-match
Do an exact match (as opposed to a substring match) in the current simple filter.

-w, --whole-pkg
Do an extended regular expression match on whole package names, assuming the syntax
of inter-package relationship fields such as Depends,Recommends, ... When this
flag is given you should not worry about sub-package names such as "libpcre3" also
matching "libpcre3-dev". This flag implies (and is incompatible with) -e.

--eq Do an equality comparison under the Debian version number system. If the pattern
or the field to be searched in is not a valid Debian version number, the paragraph
is regarded as not matching. As a special case, this is capable of comparing
simple nonnegative integers for equality.

--lt Do an strictly-less-than comparison under the Debian version number system. If the
pattern or the field to be searched in is not a valid Debian version number, the
paragraph is regarded as not matching. As a special case, this is capable of
comparing simple nonnegative integers.

--le Do an less-than-or-equal comparison under the Debian version number system. If the
pattern or the field to be searched in is not a valid Debian version number, the
paragraph is regarded as not matching. As a special case, this is capable of
comparing simple nonnegative integers.

--gt Do an strictly-greater-than comparison under the Debian version number system. If
the pattern or the field to be searched in is not a valid Debian version number,
the paragraph is regarded as not matching. As a special case, this is capable of
comparing simple nonnegative integers.

--ge Do an greater-than-or-equal comparison under the Debian version number system. If
the pattern or the field to be searched in is not a valid Debian version number,
the paragraph is regarded as not matching. As a special case, this is capable of
comparing simple nonnegative integers.

Combining filters
-!, --not, !
Match if the following filter does not match.

-o, --or
Match if either one or both of the preceding and following filters matches.

-a, --and
Match if both the preceding and the following filter match.

( ... )
Parentheses can be used for grouping. Note that they need to be escaped for most
shells. Filter modifiers can be given before the opening parentheses; they will be
treated as if they had been repeated for each simple filter inside the parentheses.

Output format modifiers
-l, --files-with-matches
Output only the file names, each on its own line, of those files that contain at
least one matching paragraph. This is incompatible with the -v and -L options, and
all other output format modifiers will be ignored.

-L, --files-without-matches
Output only the file names, each on its own line, of those files that do not
contain any matching paragraphs. This is incompatible with the -v and -l options,
and all other output format modifiers will be ignored.

-s field,field, ... | --show-field=field,field, ...
Show only the body of these fields from the matching paragraphs. The field names
must not include any colons or commas. Commas are used to delimit field names in
the argument to this option. The fields are shown in the order given here. See
also the option -I. Note that in the absence of the --ensure--dctrl option, if
only one field is selected, no paragraph separator is output.

-I, --invert-show
Invert the meaning of option -s: show only the fields that have not been named
using a -s option. As an artefact of the implementation, the order of the fields
in the original paragraph is not preserved.

A field specification can contain a colon. In such a case, the part up to the colon is
taken as the name of the field to be shown, and the part after the colon is taken as the
name of the field whose content is to be used if the field to be shown is empty.

-d Show only the first line of the Description field from the matching paragraphs. If
no -s option is specified, this option also effects -s Description; if there is a
-s option but it does not include the Description field name, one is appended to
the option. Thus the Description field's location in the output is determined by
the -s option, if any, the last field being the default.

-n, --no-field-names
Suppress field names when showing specified fields, only their bodies are shown.
Each field is printed in its original form without the field name, the colon after
it and any whitespace preceding the start of the body.

-v, --invert-match
Instead of showing all the paragraphs that match, show those paragraphs that do not
match.

-c, --count
Instead of showing the paragraphs that match (or, with -v, that don't match), show
the count of those paragraphs.

-q, --quiet, --silent
Output nothing to the standard output stream. Instead, exit immediately after
finding the first match.

Miscellaneous
--ensure-dctrl
Ensure that the output is in dctrl format, specifically that there always is an
empty line separating paragraphs. This option is not honored if the -n option has
been selected, as that option deliberately requests a non-dctrl format for the
output. In a future version, this option may be made the default behaviour.

--compat
Override any --ensure-dctrl option given earlier on the command line.

--ignore-parse-errors
Ignore errors in parsing input. A paragraph which cannot be parsed is ignored in
its entirety, and the next paragraph is assumed to start after the first newline
since the location of the error.

--debug-optparse
Show how the current command line has been parsed.

--errorlevel=level
Set log level to level. level is one of fatal, important, informational and debug,
but the last may not be available, depending on the compile-time options. These
categories are given here in order; every message that is emitted when fatal is in
effect, will be emitted in the important error level, and so on. The default is
important.

-V, --version
Print out version information.

-C, --copying
Print out the copyright license. This produces much output; be sure to redirect or
pipe it somewhere (such as your favourite pager).

-h, --help
Print out a help summary.

EXAMPLES

       The  almost simplest use of this program is to print out the status or available record of
       a package.  In this respect, grep-dctrl is like dpkg -s or dpkg --print-avail.   To  print
       out the status record of the package "mixal", do
       % grep-status -PX mixal
       and to get its available record, use
       % grep-available -PX mixal
       In  fact,  you can ask for the record of the "mixal" package from any Debian control file.
       Say, you have the Debian 6.0 CD-ROM's Packages file in the current directory; now you  can
       do a
       % grep-dctrl -PX mixal Packages

       But grep-dctrl can do more than just emulate dpkg.  It can more-or-less emulate apt-cache!
       That program has a search feature that searches package descriptions.  But we can do  that
       too:
       % grep-available -F Description foo
       searches  for  the  string  "foo"  case-sensitively  in  the descriptions of all available
       packages.  If you want case-insensitivity, use
       % grep-available -F Description -i foo
       Truth to be told, apt-cache searches package names, too.  We can separately search in  the
       names; to do so, do
       % grep-available -F Package foo
       or
       % grep-available -P foo
       which  is  pretty much the same thing.  We can also search in both descriptions and names;
       if match is found in either, the package record is printed:
       % grep-available -P -F Description foo
       or
       % grep-available -F Package -F Description foo
       This kind of search is the exactly same that apt-cache does.

       Here's one thing neither dpkg nor apt-cache do.  Search for a string in the  whole  status
       or  available file (or any Debian control file, for that matter) and print out all package
       records where we have a match.  Try
       % grep-available dpkg
       sometime and watch how thoroughly dpkg has infiltrated Debian.

       All the above queries were based on simple substring searches.  But grep-dctrl can  handle
       regular  expressions in the search pattern.  For example, to see the status records of all
       packages with either "apt" or "dpkg" in their names, use
       % grep-status -P -e 'apt|dpkg'

       Now that we have seen all these fine and dandy queries, you might begin to wonder  whether
       it is necessary to always see the whole paragraph.  You may be, for example, interest only
       in the dependency information of the packages involved.  Fine.  To show the depends  lines
       of all packages maintained by me, do a
       % grep-available -F Maintainer -s Depends 'ajk@debian.org'
       If you want to see the packages' names, too, use
       % grep-available -F Maintainer -s Package,Depends \
         'ajk@debian.org'
       Note that there must be no spaces in the argument to the -s switch.

       More  complex  queries  are  also  possible.   For  example,  to  see the list of packages
       maintained by me and depending on libc6, do
       % grep-available -F Maintainer 'ajk@debian.org' \
          -a -F Depends libc6 -s Package,Depends
       Remember that you can use other UNIX filters to help you, too.  Ever wondered,  who's  the
       most  active  Debian  developer  based  on the number of source packages being maintained?
       Easy.  You just need to have a copy of the  most  recent  Sources  file  from  any  Debian
       mirror.
       % grep-dctrl -n -s Maintainer '' Sources | sort | \
         uniq -c | sort -nr
       This  example  shows  a neat trick: if you want to selectively show only some field of all
       packages, just supply an empty pattern.

       The term "bogopackage" means the count of the packages that a Debian developer  maintains.
       To get the bogopackage count for the maintainer of dctrl-tools, say
       % grep-available -c -FMaintainer \
         "`grep-available -sMaintainer -n -PX dctrl-tools`"

       Sometimes  it  is  useful  to  output  the  data  of several fields on the same line.  For
       example, the following command outputs the list of installed  packages,  sorted  by  their
       Installed-Size.
       % grep-status -FStatus -sInstalled-Size,Package -n \
         "install ok installed" -a -FInstalled-Size --gt 0 \
         | paste -sd "  \n" | sort -n
       Note that there should be exactly 2 spaces in the "  \n" string.

       Another usual use-case is looking for packages that have another one as build dependency:
       % grep-dctrl -s Package -F Build-Depends,Build-Depends-Indep \
         quilt /var/lib/apt/lists/*Sources

       These  examples  cover  a  lot of typical uses of this utility, but not all possible uses.
       Use your imagination!  The building blocks are there, and if something's missing,  let  me
       know.

DIAGNOSTICS

In the absence of errors, the exit code 0 is used if at least one match was found, and the
exit code 1 is used if no matches were found. If there were errors, the exit code is 2,
with one exception. If the -q, --quiet or --silent options are used, the exit code 0 is
used when a match is found regardless of whether there have been non-fatal errors.

These messages are emitted in log levels fatal and important. Additional messages may be
provided by the system libraries. This list is incomplete.

A pattern is mandatory
You must specify a pattern to be searched for.

malformed filter
No filter was specified, but one is required.

cannot find enough memory
More memory was needed than was available. This error may be transient, that is,
if you try again, all may go well.

cannot suppress field names when showing whole paragraphs
When you do not use the -s switch, grep-dctrl just passes the matching paragraphs
through, not touching them any way. This means, for example, that you can only use
-n when you use -s.

inconsistent modifiers of simple filters
Conflicting modifiers of simple filters were used; for example, perhaps both -X and
-e were specified for the same simple filter.

missing ')' in command line
There were more opening than closing parentheses in the given filter.

no such log level
The argument to --errorlevel was invalid.

too many file names
The number of file names specified in the command line exceeded a compile-time
limit.

too many output fields
The argument to -s had too many field names in it. This number is limited to 256.

unexpected ')' in command line
There was no opening parenthesis that would match some closing parenthesis in the
command line.

FILES

       /var/lib/dpkg/available
              The default input file of grep-available.

       /var/lib/dpkg/status
              The default input file of grep-status.

AUTHOR

       The  program  and  this  manual page were written by Antti-Juhani Kaijanaho <gaia@iki.fi>.
       Bill Allombert <ballombe@debian.org> provided one of the examples in the manual page.