findmerge

Product	Command type
ClearCase®	cleartool subcommand

Platform
UNIX®
Linux®
Windows®

Description

For one or more versions, the findmerge command determines whether a merge is required from a specified version to the version in your view, then executes one or more actions:

Listing the versions that require a merge
Performing the required merges, checking out versions as necessary
Performing an arbitrary command

findmerge works as follows:

It considers a set of versions, which you specify using syntax similar to that of the find command.
For each of these versions, findmerge examines the relationship between the version in your view and the version specified by the –ftag, –fversion, or –flatest option. It determines whether a merge is required from that other version to your view's version.
findmerge then performs the actions you specify with –print, –exec, and/or the various –merge variants.

Keep in mind that nontrivial merge capability is guaranteed to work only for versions whose type manager implements the merge or xmerge methods. For more information, see the type_manager reference page.

Using findmerge with UCM activities

To use findmerge with UCM activities, you specify one or more activities and the option –fcsets. (The activity-selector arguments must precede the –fcsets option.) Each version listed in a change set becomes the from-version in a merge operation. As always, the to-version is the one in your view.

For other versions, for example, those of type file, the type manager may or may not be able to merge the data in the versions that findmerge identifies. For some versions, you may need to perform the merge manually, as follows:

Check out the version.
Incorporate data from the version on another branch into your checked-out version, using a text editor or some other tool.
Connect the appropriate versions with a merge arrow, using merge –ndata.

Deferring m-erges with the -print option

If you specify –print as the action (and you do not also specify any of the merge actions), findmerge does not actually perform any merges. Instead, it shows what merge activity would be required:

Needs Merge "proj.c" [to /main/41 from /main/v2_plus/6 base /main/v2_plus/3]
Log has been written to "findmerge.log.2006-11-16T17:39:18"
.
.
.

In addition, it writes a set of shell commands to perform the required merges to a log file. At some later point, you can execute the commands in the log file all at once or a few at a time.

If the directory version from which you are merging contains new files or subdirectories, findmerge –print does not report on those files or directories until you merge the directory versions. Therefore, you may want to run findmerge twice: once to merge the directory versions and again with the –print option to report which files need to be merged. You can then cancel the checkout of the directories if you do not want to save the directory merge.

Incomplete reporting of required merges

Under some circumstances, findmerge –print does not detect all the required merges (that is, all the merges that findmerge –print would perform). This occurs when one or more directory merges are required, but are not performed.

By default, findmerge merges a directory before determining merge requirements for the versions cataloged within the directory. Thus, if merging directory srcdir makes a newly created file version, patch.c, appear, findmerge proceeds to detect that patch.c itself also needs to be merged. But if the only specified action is –print, findmerge can determine only that srcdir must be merged; it cannot determine that patch.c must also be merged.

This incomplete reporting also occurs in these situations:

You decline to merge a directory when prompted by the –okmerge or –okgmerge option.
You specify –depth, which causes the versions cataloged in a directory to be processed before the directory version itself.
You use –directory or –nrecurse to suppress processing of the versions cataloged in a directory.
You use –type f, which suppresses processing of directory versions.

You can use the following procedure to guarantee that the log file produced by findmerge –print includes all the required file-level merges within the directory tree under srcdir:

Actually perform all the directory-level merges:
cmd-context findmerge srcdir –type d –merge
Generate a log file that contains the findmerge commands required for files within the merged directory hierarchy:
cmd-context findmerge srcdir –type f –print

Executing the log file produces results identical to entering the single command findmerge srcdir –merge.

findmerge algorithm

The findmerge command uses one of two algorithms to locate and examine versions. When the number of versions to be examined is below a certain threshold (approximately 100), findmerge uses the algorithm that uses the VOB's metadata. When the number of versions exceeds the threshold, findmerge uses the algorithm that requires walking through the VOB's directory structure. The directory walkthrough method is slower than the metadata method.

Options and arguments

Specifying the versions to be considered

Default: None.
pname ...: One or more file, directory versions, or both; only the specified file versions and the subtrees under the specified directory versions are considered.
–all, pname ... –all: Appending –all to a pname list causes all the versions in the VOB containing the pname to be considered, whether or not they are visible in your view. By itself, –all specifies the top-level directory of the VOB containing the current working directory.
findmerge performs additional work after processing the VOB directory tree if you use –all or –avobs in combination with –ftag; in this case, it issues a warning message for each version that is not displayed in the to-view, but is displayed in the from-view.
–avo/bs: Considers all versions in the VOBs active (mounted) on the local host in ClearCase. (If environment variable CLEARCASE_AVOBS is set to a list of VOB-tags, this set of VOBs is used instead (separate VOB tags in the list by colons (UNIX and Linux) or semicolons (Windows)).)
activity-selector ...: One or more UCM activities. Specify activity-selector in the form activity:activity-name[@vob-selector]. You must specify the –fcsets option immediately following this argument.

Specifying the from-version

Default: None. You must use one of these options to specify another version of each version, to be compared with the version in your view.
–fta/g view-tag: Compare with the version selected by your view with the version selected by the view specified by view-tag. view-tag may not specify a snapshot view. A version of the same element is always used, even if the version has a different name in the other view.
–fve/rsion version-selector: Compare with the version specified by the version-selector. A version selector involving a branch type, for example, .../branch1/LATEST, is optimized for selecting the set of versions to consider and performs better than other types of queries. If the branch exists only on a relatively small number of versions in the VOB, this option performs much better than other types of queries.
–fla/test: (Consider only versions that are currently checked out.) Compare with the most recent version on the branch from which your version was checked out. This option is useful with versions for which you have unreserved checkouts: if one or more new versions have been checked in by other users, you must merge the most recent one into your checked-out version before you can perform a checkin.
–fcs/ets: Consider all the versions in the change set of each specified activity-selector argument.

Narrowing the list of versions to be considered

Use the following options to select a subset of the versions specified by pname arguments and the –all or –avobs option.

–dep/th: Causes directory entries to be processed before the directory itself.
–nr/ecurse: For each directory version, considers the file and directory versions within it, but does not descend into its subdirectories.
–d/irectory: For each directory, considers only the directory itself, not the directory or file versions, or VOB symbolic links it catalogs.
–fol/low: Causes VOB symbolic links to be traversed.
–use/r login-name: Considers only those elements owned by user login-name.
–gro/up group-name: Considers only those elements owned by group group-name.
–typ/e f, –typ/ e d , –typ/e fd: Considers file versions only (f), directory versions only (d), or both (fd).
–nam/e pattern: Considers only those versions whose leaf names match the specified file-name pattern. (See the wildcards_ccase reference page.)
–ele/ment query: Considers only those versions that satisfy the specified query (same as the find command). A simple branch query, for example, brtype(br1), is optimized for selecting the set of versions to consider and performs better than other types of queries. When the branch exists only on a relatively small number of versions in the VOB, this option performs much better than other types of queries.

Special version tree geometry: Merging from version 0

If a merge is required from a version that happens to be version 0 on its branch, findmerge performs the merge and issues a warning message:

Element "util.c" has empty branch [to \main\6 from \main\br1\0]

More often, findmerge determines that no merge is required from a zeroth version; it handles this case as any other no-merge-required case.

The following option overrides this default behavior.

–nze/ro: Does not perform a merge if the from-contributor is version 0 on its branch. This gives you the opportunity to delete the empty branch, and then perform a merge from the version at which the branch was created.

Special version tree geometry: Merge back-and-out to subbranch

findmerge flags this special case with a warning message:

Element "msg.c" requests merge to /main/12 backwards on same branch
	from /main/18

This situation arises in these cases:

You are merging from a parent branch to a subbranch.
For a particular version, no subbranch has been created yet.
Your config spec selects a version of that version using a –mkbranch config spec rule.

In this case, findmerge performs the merge by checking out the version (which creates the subbranch at the to-version), then overwriting the checked-out version with the from-version.

The following option overrides this default behavior.

–nba/ck: Does not perform the merge in the case described earlier. It may be appropriate to simulate the merge by moving the version label down to the from-version. Note, however, that this alternative leaves the version without a subbranch, which may or may not be desirable.

Verbosity of merge analysis

findmerge does the following:

Silently skips versions that do not require a merge.
(If you use –all or –avobs in combination with –ftag) Issues a warning message if your config spec does not select any version of a version, but the config spec of the view specified with –ftag does. (For example, this occurs when a new version has been created in the from-view.)

The following options override this default behavior.

–why/not: For each version that does not require a merge, displays a message explaining the reason. This is especially useful when you are merging between views whose namespaces differ significantly.
–vis/ible: Suppresses the warning messages for versions that are not visible in the current view.

Logging of merge analysis

Default: A line is written to a merge log file for each version that requires a merge. The log takes the form of a UNIX or Linux shell script or Windows batch file that can be used to perform, at a later time, merges that are not completed automatically (see –print and –abort, for example). A number sign (#) at the beginning of a line indicates that the required merge was performed successfully. The log file's name is generated by findmerge and displayed when the command completes.
–log pname: Creates pname as the merge log file, instead of selecting a name automatically. To suppress creation of a merge log file, use –log /dev/null (UNIX and Linux) or –log NUL (Windows)

Specifying checkout comments

Default: When findmerge checks out versions to perform merges, it prompts for a single checkout comment (–cq). You can override this behavior with your .clearcase_profile file. See the comments reference page. Edit comments with chevent.
–c/omment comment | –cfi/le comment-file-pname |–cq/uery | –cqe/ach | –nc/omment: Overrides the default with the option you specify. See the comments reference page.

Affecting type of checkout

Default

If the findmerge action performs a checkout, it is a reserved checkout.

–unr/eserved [ –nma/ster ]

Performs any findmerge checkouts as unreserved checkouts.

With –nmaster, checks out the branch even if the current replica does not master the branch. Do not use this option if you cannot merge versions of the element.

For a discussion of how new versions are created from reserved and unreserved checkouts, see the checkin reference page.

Merge options

If you have findmerge perform the merges, you can specify the following options, which work exactly as they do in the merge command. (–abort and –qall are mutually exclusive.)

–q/uery: Prompts you for a choice on every change in the from-versions. Changes in the to-version are automatically accepted unless a conflict exists.
–abo/rt: Cancels a merge if it is not completely automatic.
–qal/l: Turns off automated merging. Prompts you to determine whether you want to proceed with each change.
–qnt/rivial: Turns off automated merging and prompts you to determine whether you want to proceed except in the case where a trivial merge (branch copy) would be done.
–ser/ial: Reports differences with each line containing output from one contributor, instead of in a side-by-side format.
–bla/nk_ignore: When comparing and merging files, ignores extra white space characters in text lines so that leading and trailing white space is ignored altogether and internal runs of white space characters are treated like a single space character. This option must be used with one of the merge options: –mer/ge, –okm/erge, –gm /erge, or –okg/merge.

Specifying the base contributor

Default: findmerge calculates a base contributor for a merge.
{ –bta/g | –fbt/ag } view-tag: Specifies the base view that contains the base contributor version. With –bta/g findmerge will check to see if the base contributor is a valid common ancestor, and if not, come up with its own base contributor. With –fbt/ag findmerge will not make the check.

Actions to be performed on the selected versions

Default

None.

–pri/nt [ –l/ong | –s/hort | –nxn/ame ]

Lists the names of the versions that require a merge. The default listing includes the version IDs of the to-versions and from-versions and the version ID of the base contributor (common ancestor):

Needs Merge "Makefile" [to \main\7 from \main\br1\1 base \main\6]

Specifying –short reduces the listing to version-extended path names of the to- and from-versions:

Makefile@@/main/7 Makefile@@/main/br1/1

Specifying –long adds to the default listing a description (describe command output) of the from-version:

Needs Merge "Makefile" [to /main/7 from /main/br1/1 base /main/6] version "Makefile@@/main/br1/1" created 2006-11-09T11:18:39 by Allison K. Pak (akp.user@neptune) element type: text_file predecessor version: /main/br1/0

Specifying –nxname reduces the listing to the standard path name of the version:

.\Makefile

–mer/ge –abort, –okm/erge –abort, –g/raphical, –gm/erge, –okgm/erge

(Valid only for versions whose type manager implements the merge method. See the type_manager reference page for more information.) Performs a merge for each version that requires it.

Three kinds of interfaces can be used: the –merge option performs a character-oriented merge, the –graphical option invokes the Merge Manager, and the –gmerge option invokes the graphical merge utility. All these actions attempt to check out the to-version, if it is not already checked out to your view.

The ok variants pause for verification on each version, thus allowing you to process some versions and skip others.

Special case: Specifying –merge –gmerge causes findmerge to perform a character-oriented merge in –abort mode; if the merge aborts (because it could not proceed completely automatically), the interactive graphical merge tool is invoked.

–exe/c command-invocation, –ok command-invocation

Runs the specified command for each selected version. findmerge does not perform a checkout operation when either of these options is specified. With –ok, findmerge pauses for verification on each version, thus allowing you to process some versions and skip others.

Like the find command, findmerge sets the following variables in the specified command's environment:

CLEARCASE_PN	Path name of version
CLEARCASE_XN_SFX	Extended naming symbol (default: @@)
CLEARCASE_ID_STR	Version ID of to-version
CLEARCASE_XPN	Version-extended path name of to-version
CLEARCASE_F_ID_STR	Version ID of from-version
CLEARCASE_FXPN	Version-extended path name of from-version
CLEARCASE_B_ID_STR	Version ID of base contributor version

Windows: If you invoke a command built in to the Windows shell (for example, cd, del, dir, or copy), you must invoke the shell with cmd /c. For example:

–exec 'cmd /c copy %CLEARCASE_PN% %HOME%'

If a path within command-invocation contains spaces, you must enclose it in quotation marks. For example, in cleartool single-command mode (note the backslash used to escape the second quotation mark):

–exec "cmd /c copy %CLEARCASE_PN% \"c:\findmerge results""

In cleartool interactive mode (no escape character needed):

–exec 'cmd /c copy %CLEARCASE_PN% "c:\findmerge results"'

–co

Attempts to check out the destination if it is not already checked out to your view. May be used as part one of a two-pass invocation of findmerge, where the second part uses an option such as –exec.

Examples

The UNIX and Linux examples in this section are written for use in csh. If you use another shell, you may need to use different quoting and escaping conventions.

The Windows examples that include wildcards or quoting are written for use in cleartool interactive mode. If you use cleartool single-command mode, you may need to change the wildcards and quoting to make your command interpreter process the command appropriately.

In cleartool single-command mode, cmd-context represents the UNIX or Linux shell or Windows command interpreter prompt, followed by the cleartool command. In cleartool interactive mode, cmd-context represents the interactive cleartool prompt.

On a UNIX or Linux system, compare a source file version in your current view to a version on another branch. Log the results of the comparison, but do not perform the merge. (If a merge is required, the log file stores a command that performs the merge.)
cmd-context findmerge msg.c –fversion /main/rel2_bugfix/LATEST –print

Needs Merge "msg.c" [to /main/2 from /main/rel2_bugfix/1 base /main/1] A 'findmerge' log has been written to "findmerge.log.2007-02-04T10:01:23"

cmd-context cat findmerge.log.2007-02-04T10:01:23
cleartool findmerge msg.c@@/main/2 –fver /main/rel2_bugfix/1 –log /dev/null -merge

On a Windows system, for the current directory subtree, compare all versions visible in the current view against the versions in another view. Print a list of versions that require merging, but do not perform the merge. For versions where no merge is required, explain why.

cmd-context findmerge . –ftag rel2_bugfix_view –whynot –print
 
No merge ".\Makefile" [\main\3 descended from \main\2]
No merge ".\cm_add.c" [element not visible in view rel2_bugfix_view]
No merge ".\hello.c" [to \main\4 from version zero \main\rel2_bugfix\0] 
. . . 
A 'findmerge' log has been written to "findmerge.log.2007-02-04T11:00:59" 
type findmerge.log.2007-02-04T11.00.59 
cleartool findmerge .\msg.c@@\main\2 -fver \main\rel2_bugfix\1 -log nul -merge

On a Windows system, for the current directory subtree, compare versions visible in the current view against versions on another branch and perform any required merges. The resulting log file annotates all successful merges with a number sign (#).
cmd-context findmerge . –fversion \main\rel2_bugfix\LATEST –merge

Needs Merge ".\util.c" [to \main\3 from \main\rel2_bugfix\2 base \main\rel2_bugfix\1] Comment for all listed objects:
Merge from rel2_bugfix branch.
Checked out "util.c" from version "\main\3". ******************************** <<< file 1: M:\view1\george_fig_hw\src\util.c@@\main\rel2_bugfix\1 >> file 2: .\util.c@@\main\rel2_bugfix\2 >> file 3: .\util.c ******************************** -------[changed 7-8 file 1]--------|------[changed to 7-12 file 3]----- if (user_env) | if (user_env) { return user_env; | if ( strcmp(user_env,"root") == + . . . Moved contributor ".\util.c" to ".\util.c.contrib". Output of merge is in ".\util.c". Recorded merge of ".\util.c". A 'findmerge' log has been written to "findmerge.log.2007-03-24T13.23.05"

type findmerge.log.2007-03-24T13.23.05
#cleartool findmerge .\util.c@@\main\3 -fver \main\rel2_bugfix\2 -log nul -merge -c "Merge from rel2_bugfix branch."
As in the previous commands, merge from another branch. This time, if any merge cannot be completed automatically (two or more contributors modify the same line from the base contributor), start the graphical merge utility to complete the merge.
```
cmd-context findmerge . –fversion /main/rel2_bugfix/LATEST –merge –gmerge
 
```
For the current directory subtree, compare all versions visible in the current view to versions on another branch. Follow any VOB symbolic links. Log the results of the comparison, but do not perform the merge. The current directory contains a symbolic link to the beta directory. The findmerge command follows that link and determines that version 1 of foo.c on the bugfix branch should be merged with version 4 on the main branch.
cmd-context findmerge . –fol –fversion \main\bugfix\LATEST –print

Needs Merge "\usr2\home\ktessier\testvobs\testvob\testdir\beta\foo.c" [to \main\4 from \main\bugfix\1 base \main\3] Needs Merge ".\update [to \main\4 from \main\bugfix\1 base \main\2] Log has been written to "findmerge.log.2007-07-02T14:07:49".
On a UNIX or Linux system, for the current directory subtree, compare all versions visible in the current view to versions on another branch. Do not consider versions contained in any of the current directory's subdirectories. Log the results of the comparison, but do not perform the merge. The first invocation of findmerge detects no required merges in the current directory version or the file and directory versions it contains. Invoking findmerge from the subdirectory source detects a required merge. Invoking findmerge without the –nr option at source's parent directory also detects the required merge because findmerge descends into source.
cmd-context findmerge . –nr –fversion main/bugfix/LATEST –print

% cd source
cmd-context findmerge . –nr –fversion main/bugfix/LATEST –print

Needs Merge "./update" [to /main/4 from /main/bugfix/1 base /main/2] Log has been written to "findmerge.log.2007-07-02T14:17:15".
For the current directory only, compare the directory version visible in the current view to a version on another branch. Do not consider the versions contained in those directories. Log the results of the comparison but do not perform the merge. The findmerge command discovers that the version of the directory on the rel1 branch contains a file that is not in the version of the directory visible in the current view; therefore, version 2 of the directory on the rel1 branch should be merged with version 2 on the main branch. Because the findmerge command specifies –dir, it does not evaluate this file for merging.
cmd-context findmerge . –dir –fversion \main\rel1\LATEST –print

Needs Merge "." [(automatic) to \main\2 from \main\rel1\2 (base also \main\2] Log has been written to "findmerge.log.2007-07-03T15:30:46".
Invoke the Merge Manager from the command line and complete the merge using the Merge Manager.
cmd-context findmerge . -fver .../mybranch/LATEST -graphical