aegis -MoVe_file_Undo(1)

NAME
aegis -MoVe_file_Undo - undo the rename a file as part of a change

SYNOPSIS
aegis -MoVe_file_Undo [ option... ] filename...
aegis -MoVe_file_Undo -List [ option... ]
aegis -MoVe_file_Undo -Help

DESCRIPTION
The aegis -MoVe_file_Undo command is used to reverse the effects of the aegis -MoVe_file command. You only need to name one half of the rename, the other half will be determined automatically. You may apply this command to whole directories.

The named files will be removed from the development directory, and removed from the list of files in the change.

  File Name Interpretation
The aegis program will attempt to determine the project file names from the file names given on the command line. All file names are stored within aegis projects as relative to the root of the baseline directory tree. The development directory and the integration directory are shadows of this baseline directory, and so these relative names apply here, too. Files named on the command line are first converted to absolute paths if necessary. They are then compared with the baseline path, the development directory path, and the integration directory path, to determine a baseline-relative name. It is an error if the file named is outside one of these directory trees.

The -BAse_RElative option may be used to cause relative filenames to be interpreted as relative to the baseline path; absolute filenames will still be compared with the various paths in order to determine a baseline-relative name.

The relative_filename_preference in the user configuration file may be used to modify this default behavior. See aeuconf(5) for more information.

  Process Side Effects
This command will cancel any build or test registrations, because adding another file logically invalidates them.

  Notification
The new_file_undo_command and remove_file_undo_command in the project config file are run, if set. The project_file_command is also run, if set, and if there has been an integration recently. See aepconf(5) for more information.

WHITEOUT
Aegis provides you with what is often called a “view path” which indicates to development tools (compilers, build systems, etc) look first in the development directory, then in the branch baseline, and so on up to the trunk baseline.

The problem with view paths is that in order to remove files, you need some kind of "whiteout" to say “stop looking, it's been removed.”

When you user the aerm(1) or aemv(1) commands, this means "add information to this change which will remove the file from the baseline when this change is integrated". I.e. while the change is in the being developed state, the file is only "removed" in the development directory - it's still present in the baseline, and will be until the change is successfully integrated.

When you use the aerm(1) or aemv(1) commands, Aegis will create a 1K file to act as the whiteout. It's contents are rather ugly so that if you compile or include the "removed" file accidentally, you get a fatal error. This will remind you to remove obsolete references.

When the change in integrated, the removed file is not copied/linked from the baseline to the integration directory, and is not copied from the development directory. At this time it is physically gone (no whiteout). It is assumed that because of the error inducing whiteout all old references were found and fixed while the change was in the being developed state.

  File Manifests
When generating list of files to be compiled or linked, it is important that the file manifest be generated from information known by Aegis, rather than from the file system. This is for several reasons:

(a) Aegis knows exactly what (source) files are where, whereas everything else is inferring Aegis' knowledge; and

(b) looking in the file system is hard when the view path is longer that 2 directories (and Aegis' branching method can make it arbitrarily long); and

(c) The whiteout files, and anything else left “lying around”, will confuse any method which interrogates the file system.

The easiest way to use Aegis' file knowledge is with something like an awk(1) script processing the Aegis file lists. For example, you can do this with make(1) as follows:
    # generate the file manifest
    manifest.make.inc: manifest.make.awk
    	( aegis -l cf -ter ; aegis -l pf -ter ) | \
    	awk -f manifest.make.awk > manifest.make.inc
    # now include the file manifest
    include manifest.make.inc
Note: this would be inefficient of you did it once per directory, but there is nothing stopping you writing numerous assignments into the manifest.make.inc file, all in one pass.

It is possible to do the same thing with Aegis' report generator (see aer(1) for more information), but this is more involved than the awk(1) script. However, with the information "straight from the horse's mouth" as it were, it can also be much smarter.

This file manifest would become out-of-date without an interlock to Aegis' file operations commands. By using the project-file_command and change_file_command fields of the project config file (see aepconf(5) for more information), you can delete this file at strategic times.
    /* run when the change file manifest is altered */
    change_file_command = "rm -f manifest.make.inc";
    /* run when the project file manifest is altered */
    project_file_command = "rm -f manifest.make.inc";
The new file manifest will thus be re-built during the next aeb(1) command.

  Options and Preferences
There is a -No-WhiteOut option, which may be used to suppress whiteout files when you use the aerm(1) and aemv(1) commands. There is a corresponding -WhiteOut option, which is usually the default.

There is a whiteout_preference field in the user preferences file (see aeuconf(5) for more information) if you want to set this option more permanently.

  Whiteout File Templates
The whiteout_template field of the project config file may be used to produce language-specific error files. If no whiteout template entry matches, a very ugly 1KB file will be produced - it should induce compiler errors for just about any language.

If you want a more human-readable error message, entries such as
    whiteout_template =
    [
    	{
    		pattern = [ "*.[ch]" ];
    		body = "#error This file has been removed.";
    	}
    ];
can be very effective (this example assumes gcc(1) is being used).

If it is essential that no whiteout file be produced, say for C source files, you could use a whiteout template such as
    whiteout_template =
    [
    	{ pattern = [ "*.c" ]; }
    ];
because an absent body sub-field means generate no whiteout file at all.

You may have more than one whiteout template entry, but note that the order of the entries is important. The first entry which matches will be used.

  Notification
On successful completion of this command, the notifications usually performed by the aermu(1), aenfu(1) and aentu(1) commands are run, as appropriate. These include the project_file_command, new_file_undo_command, new_test_undo_command and remove_file_undo_command fields of the project config file. See aepconf(5) for more information.

OPTIONS
The following options are understood:

-Change number
    This option may be used to specify a particular change within a project. See aegis(1) for a complete description of this option.

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

-List
    This option may be used to obtain a list of suitable subjects for this command. The list may be more general than expected.

-Not_Logging
    This option may be used to disable the automatic logging of output and errors to a file. This is often useful when several aegis commands are combined in a shell script.

-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.

-TERse
    This option may be used to cause listings to produce the bare minimum of information. It is usually useful for shell scripts.

-Verbose
    This option may be used to cause aegis to produce more output. By default aegis only produces output on errors. When used with the -List option this option causes column headings to be added.

-Verify_Symbolic_Links
    This option may be used to request that the symbolic links, or hard links, or file copies, in the work area be updated to reflect the current state of the baseline. This is controlled by the development_directory_style field of the project configuration file. Only files which are not involved in the change are updated. See also the “symbolic_links_preference” field of aeuconf(5). This option is the default, if meaningful for your configuration. The name is an historical accident, hard links and file copies are included.

-Assume_Symbolic_Links
    This option may be used to request that no update of baseline mirror files take place. This options is useful when you definitely know the files' up-to-date-ness isn't important right now; incorrect use of this option may have unanticipated build side-effects. See also the “symbolic_links_preference” field of aeuconf(5). This option is the default, if not meaningful for your configuration. The name is an historical accident, hard links and file copies are included.

-Wait
    This option may be used to require Aegis commands to wait for access locks, if they cannot be obtained immediately. Defaults to the user's lock_wait_preference if not specified, see aeuconf(5) for more information.

-No_Wait
    This option may be used to require Aegis commands to emit a fatal error if access locks cannot be obtained immediately. Defaults to the user's lock_wait_preference if not specified, see aeuconf(5) for more information.

-WhiteOut
    This option may be used to request that deleted files be replaced by a “whiteout” file in the development directory. The idea is that compiling such a file will result in a fatal error, in order that all references may be found. This is usually the default.

-No_WhiteOut
    This option may be used to request that no “whiteout” file be placed in the development directory.

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 aegis are long, this means ignoring the extra leading '-'. The "--option=value" convention is also understood.

RECOMMENDED ALIAS
The recommended alias for this command is
csh%	alias aemvu 'aegis -mvu \!* -v'
sh$	aemvu(){aegis -mvu "$@" -v}

ERRORS
It is an error if the change is not in the being developed state.
It is an error if the change is not assigned to the current user.
It is an error if the file is not being moved by the change.

EXIT STATUS
The aegis command will exit with a status of 1 on any error. The aegis 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.

SEE ALSO

aecp(1)
    copy files into a change

aedb(1)
    begin development of a change

aemv(1)
    rename files as part of a change

aenf(1)
    add files to be created by a change

aenfu(1)
    remove files to be created by a change

aerm(1)
    add files to be deleted by a change

aermu(1)
    remove files to be deleted by a change

aeuconf(5)
    user configuration file format

COPYRIGHT
aegis version 4.24.2.D001
Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 20 Peter Miller

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

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