gnupg/doc/gpg.1pod

=head1 NAME

gpg - GNU Privacy Guard

=head1 SYNOPSIS

B<gpg> [--homedir name] [--options file] [options] command [args]

=head1 DESCRIPTION

This is the main program from the GNUPG system.

=head1 COMMANDS

B<gpg> recognizes these commands:

B<-s>, B<--sign>
    Make a signature. This option maybe combined
    with B<--encrypt>.

B<--clearsign>
    Make a clear text signature.

B<-b>, B<--detach-sign>
    Make a detached signature.

B<-e>, B<--encrypt>
    Encrypt data. This option may be combined with B<--sign>.

B<-c>, B<--symmetric>
    Encrypt only with symmetric cipher
    This command asks for a passphrase.

B<--store>
    store only (make a RFC1991 packet).

B<-d>, B<--decrypt>
    Decrypt data. This is the default operation for data
    files.

B<-k> [I<keyring>]
    Kludge to be somewhat compatibe to PGP.
    Without arguments, all public key-rings are listed,
    with one argument, only I<keyring> is listed.
    Special combinations are also allowed, but it may
    give starnge results when combined with more options.
    B<-kv>    Same as B<-k>
    B<-kvv>   List the signatures with every key.
    B<-kvvv>  Additional check all signatures.
    B<-kvc>   List fingerprints
    B<-kvvc>  List fingerprints and signatures

B<--list-keys>
    List all keys in all public key-rings and check the
    signatures.

B<--check-keys>
    Check signatures on a key in the keyring

B<--fingerprint>
    Show the fingerprints

B<--list-packets>
    List only the sequence of packets. This is mainly
    useful for debugging.

B<--gen-key>
    Generate a new key pair. This command can only be
    used interactive.

B<--sign-key> I<name>
    Make a signature on key of user I<name>.
    This looks for the key, displays the key and checks
    all existing signatures of this key. If the key is
    not yet signed by the default user (or the users given
    with B<-u>), the program displays the information of
    the key again, together with it's fingerprint and
    asked whether it should be signed. This question
    is repeated for all users specified with B<-u>.
    The key is then signed and the keyring which
    contains the key is updated.


B<--delete-key>
    Remove key from the public keyring

B<--edit-sig>
    Edit/remove a key signature.

B<--change-passphrase>
    Change the passphrase of your secret keyring

B<--gen-revoke>
    Generate a revocation certificate.

B<--export> [I<names>]
    Either export all keys from all key-rings (default
    key-rings and those registered via option B<--keyring>,
    or if at least one name is given, those of the given
    name. The new keyring is written to F<stdout> or to
    the file given with option "output".  Use together
    with B<-a> to mail those keys.

B<--import>
    import/merge keys


=head1 OPTIONS

Long options can be put in an options file (default F<~/.gnupg/options>);
do not write the 2 dashes, but simply the name of the option and any
arguments if required, lines with a hash as the first non-white-space
character are ignored. Commands maybe put in this file too, but that
does not make sense.

B<gpg> recognizes these options:


B<-a>, B<--armor>
    Create ASCII armored output.

B<-o> I<file>, B<--output> I<file>
    Write output to I<file>.

B<-u> I<name>, B<--local-user> I<name>
    Use I<name> as the user-id to sign.

B<-r>  I<name>, B<--remote-user>  I<name>
    Use  I<name> as the user-id for encryption.

B<-v>, B<--verbose>
    Give more informations during processing. If used
    2 times, the input data is listed in detail.


B<-z> I<n>
    Set compress level to I<n>. A value of 0 for I<n>
    disables compression. Default is to use the default
    compression level of zlib (which is 6).

B<-t>, B<--textmode>
    Use canonical text mode.  Used to make clear-text
    signatures.

B<-n>, B<--dry-run>
    Don't make any changes (not yet implemented).

B<--batch>
    Batch mode; never ask, do not allow interactive
    commands.

B<--no-batch>
    Disable batch mode; this may be used if B<batch>
    is used in the options file.

B<--yes>
    Assume yes on most questions.

B<--no>
    Assume no on most questions.

B<--keyring> I<file>
    Add I<file> to the list of key-rings.
    If I<file> begins with a tilde and a slash, these
    are replaced by the HOME directory. If the filename
    does not contain a slash, it is assumed to be in the
    home-directory (F<~/.gnupg> if B<--homedir>) is not used.

B<--secret-keyring> I<file>
    Same as B<--keyring> but for secret key-rings.

B<--homedir> I<dir>
    Set the name of the home directory to I<dir>. If this
    option is not used it defaults to F<~/.gnupg>. It does
    not make sense to use this in a options file. This
    also overrides the environment variable C<GNUPGHOME>.

B<--options> I<file>
    Read options from I<file> and do not try to read
    them from the default options file in the homedir
    (see B<--homedir>). This option is ignored when used
    in an options file.

B<no-options>
    Shortcut for B<--options> I</dev/null>.  This option is
    detected before an attempt to open an option file.

B<--debug> I<flags>
    Set debugging flags. All flags are or-ed and I<flags> may
    be given in C syntax (e.g. 0x0042).

B<--debug-all>
    Set all useful debugging flags.

B<--status-fd> I<n>
    Write special status strings to the file descriptor I<n>.

B<--no-comment>
    Do not write comment packets.

B<--completes-needed> I<n>
    Number of completey trusted users to introduce a new
    key signator (defaults to 1).

B<--marginals-needed> I<n>
    Number of marginally trusted users to introduce a new
    key signator (defaults to 3)

B<--cipher-algo> I<name>
    Use I<name> as cipher algorithm. Running the program
    with the option B<--verbose> yields a list off supported
    algorithms.

B<--pubkey-algo> I<name>
    Use I<name> as puplic key algorithm. Running the program
    with the option B<--verbose> yields a list off supported
    algorithms.

B<--digest-algo> I<name>
    Use I<name> as message digest algorithm. Running the
    program with the option B<--verbose> yields a list off
    supported algorithms.

B<--passphrase-fd> I<n>
    Read the passphrase from file descriptor I<n>. If you use
    0 for I<n>, the passphrase will be read from stdin.  This
    can only be used if only one passphrase is supplied.
    B<Don't use this option if you can avoid it>

B<no-verbose>
    Reset verbose level to 0.

B<no-greeting>
    Suppress the initial copyright message but do not
    enter batch mode.

B<no-armor>
    Assume the input data is not in ASCCI armored format.

B<no-default-keyring>
    Do not add the default key-rings to the list of
    key-rings.

B<--version>
    Print version information along with a list
    of supported algorithms.

B<--warranty>
    Print warranty information.

B<-h>, B<--help>
    Print usage information.


=head1 RETURN VALUE

The Program returns 0 if everything was fine, 1 if at least
a signature was bad and other errorcode for fatal errors.

=head1 EXAMPLES

  -se -r Bob [file]	     sign and encrypt for user Bob
  -sat [file]		     make a clear text signature
  -sb  [file]		     make a detached signature
  -k   [userid] 	     show keys
  -kc  [userid] 	     show fingerprint

=head1 ENVIRONMENT

C<HOME>       Used to locate the default home directory.
C<GNUPGHOME>  If set, direcory used instead of F<~/.gnupg>.

=head1 FILES

F<~/.gnupg/secring.gpg>     The secret key-ring

F<~/.gnupg/pubring.gpg>     The public key-ring

F<~/.gnupg/trustdb.gpg>     The trust database

F<~/.gnupg/gnupg.gpg>	    Signature of GNUPG files.

F<~/.gnupg/options>	    May contain options


=head1 SEE ALSO

gpgm(1)  gpgk(1)


=head1 WARNINGS

Use a B<good> password for your user account and a non-simple passphrase
to protect your secret key.

Keep in mind that, if this program is used over a network (telnet), it
is B<very> easy to spy out your passphrase!