NAME

        aelock - take a lock while a command runs

SYNOPSIS

        aelock [ option...  ] command
        aelock -Help
        aelock -VERSion

DESCRIPTION

        The aelock" command is used to take a project lock while a command runs.  This may be
        used to ensure that the project state is stable while it is being backed up.

        The named command is looked for as an attribute called aelock:command within the
        project_specific field of the project configuration file.

        The command is then passed through the usual aesub(5) substitutions before being
        executed.  The command is executed as the project owner.  If the command returns with a
        non-zero exit status, the aelock(1) command will return an exit status of one.

   Security Issues
        This command is a potential security problem.  Because it takes a read-only lock of all
        active branches and changes in a project, from the trunk down, misuse of this command is
        a potential denial of service attack.  Thus, this command is limited to project
        administrators only.

        This command could have been designed to take an arbitrary command to execute, like
        sudo(1), but this would have granted users, even project administrators, more privileges
        than usual.  For this reason, the command is held in a source controlled, fully reviewed
        project configuration file, and is simply indicated by name.

        The command is run as the project owner, not the executing user.  It has full write
        access (that's the way Unix permissions work).  Like aeb(1), this means it can wreak
        havoc on the project baseline and meta-data.  Use with extreme care.

OPTIONS

        The following options are understood:

        -Project name
                This option may be used to select the project of interest.  When no -Project
                option is specified, the AEGIS_PROJECT environment variable is consulted.  If
                that does not exist, the user's $HOME/.aegisrc file is examined for a default
                project field (see aeuconf(5) for more information).  If that does not exist,
                when the user is only working on changes within a single project, the project
                name defaults to that project.  Otherwise, it is an error.

        -Help
                This option may be used to obtain more information about how to use the aelock
                program.

        See also aegis(1) for options common to all aegis commands.

        All options may be abbreviated; the abbreviation is documented as the upper case letters,
        all lower case letters and underscores (_) are optional.  You must use consecutive
        sequences of optional letters.

        All options are case insensitive, you may type them in upper case or lower case or a
        combination of both, case is not important.

        For example: the arguments "-project, "-PROJ" and "-p" are all interpreted to mean the
        -Project option.  The argument "-prj" will not be understood, because consecutive
        optional characters were not supplied.

        Options and other command line arguments may be mixed arbitrarily on the command line,
        after the function selectors.

        The GNU long option names are understood.  Since all option names for aelock are long,
        this means ignoring the extra leading '-'.  The "--option=value" convention is also
        understood.

EXIT STATUS

        The aelock command will exit with a status of 1 on any error.  The aelock command will
        only exit with a status of 0 if there are no errors.

ENVIRONMENT VARIABLES

        See aegis(1) for a list of environment variables which may affect this command.  See
        aepconf(5) for the project configuration file's project_specific field for how to set
        environment variables for all commands executed by Aegis.

COPYRIGHT

        aelock version 4.24.3.D001
        Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
        2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Peter Miller

        The aelock program comes with ABSOLUTELY NO WARRANTY; for details use the 'aelock
        -VERSion License' command.  This is free software and you are welcome to redistribute it
        under certain conditions; for details use the 'aelock -VERSion License' command.

AUTHOR

        Peter Miller   E-Mail:   millerp@canb.auug.org.au
        /\/\*             WWW:   http://www.canb.auug.org.au/~millerp/