findmerge

Searches for elements that require a merge /optionally perform merge

APPLICABILITY

ClearCase (cleartool subcommand), Attache (command)

SYNOPSIS

DESCRIPTION

For one or more elements, 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:

findmerge works as follows:

  1. It considers a set of elements, which you specify using syntax similar to that of the ClearCase/Attache find command.
  2. For each of these elements, 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.
  3. findmerge then performs the actions you specify with -print, -exec, and/or the various -merge variants. (In Attache, if merges are performed, the resulting merged files are left in your workspace.
  4. (Attache only) Local directories are not updated after a directory merge; the user must issue get commands to update merged directories.

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

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.

(ClearCase only) For other elements-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 elements, you may need to perform the merge manually, as follows:

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

(Attache only) For some elements, namely, those not containing text, you need to perform the merge manually, as follows:

  1. Check out the element
  2. Incorporate data from the version on another branch into your checked-out version, using a text editor or some other tool
  3. Connect the appropriate versions with a merge arrow, using merge -ndata
Deferring Merges 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.16-Nov-98.17:39:18"

.
.
.

In addition, it writes a set of shell commands to perform the required merges to a log file. In Attache, the log file is in the view:

cleartool findmerge proj.c@@\main\41 -fver \main\v2_plus\6 -log nul -merge -cqe

.
.
.

At some later point, you can execute the commands in the log file-all at once, or a few at a time. In Attache, the commands in the log file can be executed only on the helper host.

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 -merge would perform). This occurs if one or more directory merges are required, but are not performed.

By default, findmerge merges a directory before determining merge requirements for the elements cataloged within the directory. Thus, if merging directory srcdir makes a newly created file element, patch.c, appear, findmerge proceeds to detect that patch.c itself also needs to be merged. But if the only specified action is -print, then 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 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:

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

In ClearCase, 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 elements. When the number of elements to be examined is below a certain threshold (approximately 100), findmerge uses the algorithm that uses the VOB's metadata. When the number of elements 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.

PERMISSIONS AND LOCKS

Any user can enter a findmerge command. If the specified action involves checking out and/or merging files, you must have the appropriate permissions for those commands. See the checkout and merge reference pages for more information.

OPTIONS AND ARGUMENTS

SPECIFYING THE ELEMENTS TO BE CONSIDERED.  Default: None.

pname ...

One or more file and/or directory elements; only the specified file elements and the subtrees under the specified directory elements are considered.
In Attache, arguments of the form @pname can be used to add the contents of the local file pname as pathname arguments. The pathname arguments can contain wildcards (see the wildcards reference page), and must be listed in the file one per line, or also be of the form @pname. Specifying a relative pathname for @pname begins from Attache's startup directory, not the working directory, so a full local pathname is recommended.
-all
pname ... -all

Appending -all to a pname list (or an @pname list in Attache) causes all the elements 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 element that does not appear in the to-view, but does appear in the from-view.
-avo·bs

Considers all elements in the VOBs active (mounted) on the local host in ClearCase or on the helper host in Attache. (If environment variable CLEARCASE_AVOBS is set to a semicolon-separated list of VOB-tags, this set of VOBs is used instead. In Attache, the environment variable must be set in the helper process.)
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 element, to be compared with the version in your view.

-fta·g view-tag

Compare with the version in the view with the version in 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 element 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 elements to consider and performs better than other types of queries. In the case where the branch exists only on a relatively small number of elements in the VOB, this option performs much better than other types of queries.
-fla·test

(Consider only elements 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 elements 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 ELEMENTS TO BE CONSIDERED.  Use the following options to select a subset of the elements 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 element, considers the file and directory elements within it, but does not descend into its subdirectories.
-d·irectory

For each directory, considers only the directory itself, not the directory or file elements, 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 belonging to group group-name.
-typ·e f
-typ·e d
-typ·e fd

Considers file elements only (f), directory elements only (d), or both (fd).
-nam·e pattern

Considers only those elements whose leaf names match the specified file-name pattern. (See the wildcards_ccase or wildcards (Attache) reference page.)
-ele·ment query

Considers only those elements that satisfy the specified query (same as the ClearCase or Attache find command). A simple branch query, for example, brtype(br1), is optimized for selecting the set of elements to consider and performs better than other types of queries. When the branch exists only on a relatively small number of elements 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's default behavior is to perform the merge and issue 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. Figure 11 illustrates these cases.

Figure 11 Merging From the Zeroth Version on a Branch

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:

In this case, findmerge's default behavior is to perform the merge by checking out the element (which creates the subbranch at the to-version), then overwriting the checked-out version with the from-version. Figure 12 illustrates this case.

Figure 12 Merging Back and Out to a Subbranch

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 element without a subbranch, which may or may not be desirable.

VERBOSITY OF MERGE ANALYSIS.  By default, findmerge:

The following options override this behavior.

-why·not

For each element 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 elements that are not visible in the current view.

LOGGING OF MERGE ANALYSIS.  Default: A line is written to a merge log file (in Attache, in the working directory in the view) for each element that requires a merge. The log takes the form of a batch file that can be used to perform, at a later time (in Attache, on the helper host), 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.

NOTE: In Attache, the log file can be executed later, but the results may differ since copies of versions in the workspace are not taken into account. The commands can be cut and pasted from this log into the Attache command window, which will work correctly.

-log pname

Creates pname as the merge log file (in Attache, on the helper host), instead of selecting a name automatically. To suppress creation of a merge log file, use -log NUL.

SPECIFYING CHECKOUT COMMENTS.  Default: When findmerge checks out elements in order to perform merges, it prompts for a single checkout comment (-cq). You can override this behavior with your .clearcase_profile file. See CUSTOMIZING COMMENT HANDLING in 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

Performs any findmerge checkouts as unreserved checkouts.

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

-q·uery (ClearCase only)

Turns off automatic merging for nontrivial merges and prompts you to proceed with every change in the from-versions. Changes in the to-version are accepted unless a conflict exists.
-abo·rt

Cancels a merge if it is not completely automatic. In Attache, -abort is required with -merge and -okmerge.
-qal·l

Turns off automated merging. In Attache, turns off automated merging when in graphical mode. Prompts you to determine whether you want to proceed with each change.
-ser·ial

Reports differences with each line containing output from one contributor, instead of in a side-by-side format.

ACTIONS TO BE PERFORMED ON THE SELECTED ELEMENTS.  Default: None.

-pri·nt [ -l·ong | -s·hort | -nxn·ame ]

Lists the names of the elements that require a merge. The default listing includes the version-IDs of the to-versions and from-versions, and that 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 pathnames 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 09-Nov-98.11:18:39 by Allison K. Pak (akp.user@neptune)
  element type: text_file
  predecessor version: \main\br1\0
Specifying -nxname reduces the listing to just the standard pathname of the element:
.\Makefile
-mer·ge -abort (-abort only with Attache)
-okm·erge -abort (-abort only with Attache)
-g·raphical
-gm·erge
-okgm·erge

(Valid only for elements whose type manager implements the merge method. See the type_manager reference page for more information.) Performs a merge for each element that requires it.
Three kinds of interfaces can be used: the -merge option performs a character-oriented merge, the -graphical option invokes the ClearCase 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. In Attache, only noninteractive merges are allowed in character mode; interactive merges must be done in graphical mode.
The ok variants pause for verification on each element, thus allowing you to process some elements 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 element. findmerge does not perform a checkout operation when either of these options is specified. With -ok, findmerge pauses for verification on each element, thus allowing you to process some elements and skip others.
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 embed 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"'
Like the ClearCase and Attache find command, findmerge sets the following variables in the specified command's environment:

CLEARCASE_PN

Pathname of element

CLEARCASE_XN_SFX

Extended naming symbol (default: @@)

CLEARCASE_ID_STR

Version-ID of to-version

CLEARCASE_XPN

Version-extended pathname of to-version

CLEARCASE_F_ID_STR

Version-ID of from-version

CLEARCASE_FXPN

Version-extended pathname of from-version

CLEARCASE_B_ID_STR

Version-ID of base contributor version

-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

Examples including 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 command interpreter prompt. In cleartool interactive mode, cmd-context represents the interactive cleartool prompt. In Attache, cmd-context represents the workspace prompt.

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.04-Feb-99.10:01:23"
> type findmerge.log.04-Feb-99.10.01.23
cleartool findmerge msg.c@@\main\2 -fver \main\rel2_bugfix\1 -log nul -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.04-Feb-99.10:01:23"
cmd-context shell type findmerge.log.04-Feb-99.10:01:23
cleartool findmerge msg.c@@/main/2 -fver /main/rel2_bugfix/1 -log /dev/null -merge
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.04-Feb-99.11:00:59"
type findmerge.log.04-Feb-99.11.00.59
cleartool findmerge .\msg.c@@\main\2 -fver \main\rel2_bugfix\1 -log nul -merge
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.04-Feb-99.11:00:59"
shell type findmerge.log.04-Feb-99.11.00.59
cleartool findmerge .\msg.c@@\main\2 -fver \main\rel2_bugfix\1 -log nul -merge
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.24-Mar-99.13.23.05"
type findmerge.log.24-Mar-99.13.23.05
#cleartool findmerge .\util.c@@\main\3 -fver \main\rel2_bugfix\2 -log nul -merge -c "Merge from rel2_bugfix branch."
cmd-context findmerge . -fversion \main\rel2_bugfix\LATEST -merge -abort
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") == +
.
.
.
Output of merge is in ".\util.c".
Recorded merge of ".\util.c".
A 'findmerge' log has been written to "findmerge.log.24-Mar-99.13.23.05"
cmd-context shell type findmerge.log.24-Mar-99.13.23.05
#cleartool findmerge .\util.c@@\main\3 -fver \main\rel2_bugfix\2 -log nul -merge -c "Merge from rel2_bugfix branch."
cmd-context findmerge . -fversion \main\rel2_bugfix\LATEST -merge -gmerge
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.02-Jul-99.14:07:49".
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.02-Jul-99.14:17:15".
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.03-Jul-99.15:30:46".
findmerge . -fver .../mybranch/LATEST -graphical

SEE ALSO

find, merge, update



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