doc/apt-cache.8

   1 .\" This manpage is copyright (C) 1998 Branden Robinson <branden@debian.org>.
   2 .\"
   3 .\" This is free software; you may redistribute it and/or modify
   4 .\" it under the terms of the GNU General Public License as
   5 .\" published by the Free Software Foundation; either version 2,
   6 .\" or (at your option) any later version.
   7 .\"
   8 .\" This is distributed in the hope that it will be useful, but
   9 .\" WITHOUT ANY WARRANTY; without even the implied warranty of
  10 .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 .\" GNU General Public License for more details.
  12 .\"
  13 .\" You should have received a copy of the GNU General Public
  14 .\" License along with APT; if not, write to the Free Software
  15 .\" Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  16 .\" 02111-1307 USA
  17 .TH apt-cache 8 "16 June 1998" "Debian GNU/Linux"
  18 .SH NAME
  19 apt-cache \- APT package handling utility \(em cache manipulator
  20 .SH SYNOPSIS
  21 .B apt-cache
  22 .I command cache
  23 .RI [ argument
  24 .IR ... ]
  25 .SH DESCRIPTION
  26 .B apt-cache
  27 performs a variety of operations on APT's package cache.
  28 .I apt-cache
  29 is seldom called directly; instead it is usually invoked internally by
  30 .BR apt-get (8)
  31 or
  32 .BR apt (8).
  33 .PP
  34 .I command
  35 is one of
  36 .RS
  37 .PD 0
  38 .B add
  39 .PP
  40 .B dump
  41 .PP
  42 .B dumpavail
  43 .PP
  44 .B showpkg
  45 .PP
  46 .B stats
  47 .RE
  48 .PD 1
  49 .PP
  50 .I cache
  51 must be a package cache file (for instance,
  52 .IR /var/cache/apt/pkgcache.bin ).
  53 Some
  54 .IR command s
  55 require additional arguments.
  56 .SS add
  57 .B add
  58 adds a new set of package records to
  59 .IR cache .
  60 Remaining arguments are of the form
  61 .IR file : dist : ver ,
  62 where
  63 .I file
  64 is the full path to file in question.
  65 .I dist
  66 and
  67 .I ver
  68 can be any string and are not yet implemented.
  69 .SS dump
  70 .B dump
  71 displays information about all the packages in the cache. See
  72 .B showpkg
  73 below for an explanation of what data is output for each package.
  74 .SS dumpavail
  75 .B dumpavail
  76 generates an
  77 .I available
  78 file suitable for use with
  79 .BR dpkg (8)
  80 based on the information in the cache.
  81 .SS showpkg
  82 .B showpkg
  83 displays information about the packages listed on the command line.
  84 Remaining arguments are package names. The available versions and
  85 reverse dependencies of each package listed are listed, as well as
  86 forward dependencies for each version. Forward (normal) dependencies
  87 are those packages upon which the package in question depends; reverse
  88 dependencies are those packages that depend upon the package in
  89 question. Thus, forward dependencies must be satisfied for a package,
  90 but reverse dependencies need not be.
  91 For instance,
  92 .B apt-cache showpkg
  93 .I cache
  94 .B libreadline2
  95 would produce output similar to the following:
  96 .PP
  97 .RS
  98 .PD 0
  99 Package: libreadline2
 100 .PP
 101 Versions: 2.1-8,2.1-7,
 102 .PP
 103 Reverse Depends:
 104 .RS
 105 .PP
 106 libreadlineg2,libreadline2
 107 .PP
 108 libreadlineg2,libreadline2
 109 .PP
 110 libreadline2-altdev,libreadline2
 111 .RE
 112 .PP
 113 Dependencies:
 114 .PP
 115 2.1-8 - libc5 ncurses3.0 ldso
 116 .PP
 117 2.1-7 - ldso libc5 ncurses3.0
 118 .RE
 119 .PD 1
 120 .PP
 121 Thus it may be seen that libreadline2, version 2.1-8, depends on libc5,
 122 ncurses3.0, and ldso, which must be installed for libreadline2 to work. In
 123 turn, libreadlineg2 and libreadline2-altdev depend on libreadline2. If
 124 libreadline2 is installed, libc5, ncurses3.0, and ldso must also be
 125 installed; libreadlineg2 and libreadline2-altdev do not have to be
 126 installed.
 127 .SS stats
 128 .B stats
 129 displays some statistics about
 130 .IR cache .
 131 No further arguments are expected. Statistics reported are:
 132 .RS
 133 .TP
 134 .I Total package names
 135 is the number of package names found in the cache.
 136 .TP
 137 .I Normal packages
 138 is the number of regular, ordinary package names; these
 139 are packages that bear a one-to-one correspondence between their names and
 140 the names used by other packages for them in dependencies. The majority of
 141 packages fall into this category.
 142 .TP
 143 .I Pure virtual packages
 144 is the number of packages that exist only as a virtual package name; that
 145 is, packages only "provide" the virtual package name, and no package
 146 actually uses the name. For instance, "mail-transport-agent" in the Debian
 147 GNU/Linux system is a pure virtual package; several packages provide
 148 "mail-transport-agent", but there is no package named "mail-transport-agent".
 149 .TP
 150 .I Single virtual packages
 151 is the number of packages with only one package providing a particular
 152 virtual package. For instance, in the Debian GNU/Linux system,
 153 "X11-text-viewer" is a virtual package, but only one package, xless,
 154 provides "X11-text-viewer".
 155 .TP
 156 .I Mixed virtual packages
 157 is the number of packages that either provide a particular virtual package
 158 or have the virtual package name as the package name. For instance, in the
 159 Debian GNU/Linux system, e2fsprogs is both an actual package, and
 160 provided by the e2compr package.
 161 .TP
 162 .I Missing
 163 is the number of package names that were referenced in a dependency but
 164 were not provided by any package. Missing packages may be in evidence
 165 if a full distribution is not accesssed, or if a package (real or virtual)
 166 has been dropped from the distribution.
 167 .TP
 168 .I Total distinct versions
 169 is the number of package versions found in the cache; this value is
 170 therefore at least equal to the number of total package names. If more than
 171 one distribution (both "stable" and "unstable", for instance), is being
 172 accessed, this value can be considerably larger than the number of total
 173 package names.
 174 .TP
 175 .I Total dependencies
 176 is the number of dependency relationships claimed by all of the packages in
 177 the cache.
 178 .RE
 179 .SH OPTIONS
 180 None.
 181 .SH FILES
 182 None.
 183 .SH SEE ALSO
 184 .BR apt (8),
 185 .BR apt-get (8),
 186 .I /usr/doc/apt/cache*
 187 .SH DIAGNOSTICS
 188 apt-cache returns zero on normal operation, decimal 100 on error.
 189 .SH BUGS
 190 See <http://www.debian.org/Bugs/db/pa/lapt.html>.  If you wish to report a
 191 bug in
 192 .BR apt-cache ,
 193 please see
 194 .I /usr/doc/debian/bug-reporting.txt
 195 or the
 196 .BR bug (1)
 197 command.
 198 .SH AUTHOR
 199 apt-cache was written by the APT team <apt@packages.debian.org>.