diffcr

Compares configuration records created by clearmake, omake, or clearaudit

Applicability


Product	Command type
ClearCase®	cleartool subcommand


Platform
UNIX
Linux
Windows

Synopsis

diffcr [ –r/ecurse | –fla/t ] [ –sel/ect do-leaf-pattern ]

[ –ci ] [ –typ/e { f | d | l } ... ]

[ –ele/ment_only ] [ –vie/w_only ]

[ –cri/tical_only ] [ –nam/e tail-pattern ]

[ –wd ] [ –nxn/ame ] [ –fol/low ] [ –l/ong | –s/hort ]

do-pname-1 do-pname-2

Description

The diffcr command compares the configuration records (CRs) of two derived objects. A CR is produced by clearmake, clearaudit, and omake when they finish executing a build script in a dynamic view. By comparing CRs, you can determine these differences:

Versions of MVFS objects used as sources or produced during the build (includes elements and other objects whose pathnames are under a VOB mount point)
Versions of non-MVFS objects that appeared as makefile dependencies during the build (explicit dependencies declared in the makefile)
The total number of times an object was referenced during a build, and the first target in which that object was referenced
Build options (which can come from the command line, the operating system environment, the makefile itself, and so on)
The build script executed
Noncritical differences, such as the date/time of the build, dynamic view name, or host name

Note: Not all of this information is available from configuration records of DOs created by clearaudit.

The do-pname arguments specify the derived objects to be compared. You can specify a derived object in these ways:

Use a derived-object ID (DO ID), which identifies a derived object created in any dynamic view. A DO ID takes the following form:
DO-pname@@creation_date.creation_time.id-number

For example:

myprog.o@@2006-11-11T17:39.3871

To display a derived object's DO ID, use lsdo.
Use a standard pathname, which identifies a DO created in the current dynamic view, for example, myprog.obj.
Use a view-extended pathname, which identifies a DO created in another dynamic view, for example, /view/jpb/usr/src/myprog.o.

You can compare a nonshareable DO in your view to a nonshareable DO created in another view, but you must use a view-extended path name to specify the DO in the other view.

diffcr supports the same filter and report style options as the catcr command. This support allows you to restrict the comparison to particular subtargets of the do-pname, control which objects appear in the listing, specify how path names are displayed, and expand the listing to include comments and other supplementary information. For additional information, see the catcr reference page.

DOs in unavailable views

diffcr maintains a cache of tags of inaccessible views. For each view tag, the command records the time of the first unsuccessful contact. Before trying to access a view, the command checks the cache. If the view's tag is not listed in the cache, the command tries to contact the view. If the view's tag is listed in the cache, the command compares the time elapsed since the last attempt with the time out period specified by the CCASE_DNVW_RETRY environment variable. If the elapsed time is greater than the time out period, the command removes the view tag from the cache and tries to contact the view again.

The default time out period is 60 minutes. To specify a different time out period, set CCASE_DNVW_RETRY to another integer value (representing minutes). To disable the cache, set CCASE_DNVW_RETRY to 0.

Restrictions

None.

Options and arguments

Comparing differences in subtargets

Default: diffcr compares the CRs for do-pname-1 and do-pname-2 only, not for any of their subtargets.
–r/ecurse: Compares the CRs of the two specified derived objects and their common subtargets. Each pair of CRs is compared separately. By default, a recursive comparison does not descend into DO versions; use –ci to override this behavior.
–fla/t: Similar to –recurse, but consolidates the CRs for each do-pname-n into a single list, with no duplicates and then compares the lists. The report includes file system objects only—no headers, variables and options, or build scripts. It also includes the total number of times that each object was referenced during the build and the first target in which each object was referenced (First seen in target).
–sel/ect do-leaf-pattern: Starts the comparison at the subtargets of do-pname that match do-leaf-pattern (which can include pattern-matching characters; see the wildcards_ccase reference page). This option is useful for focusing on a particular object (for example, object module hello.obj) that was built as part of a larger object (for example, executable hello.exe).
–ci (for use with –recurse or –flat only): Descends into the CRs of DO versions that were used as build sources.

Specifying kinds of objects to display

Default: On UNIX and Linux systems, diffcr reports on all objects in the CRs, which may include source files, directories, and symbolic links; derived objects; makefiles; view-private files, and non-MVFS objects that were explicitly declared as dependencies.
On Windows systems, diffcr reports on all objects in the CRs, which may include source files and directories; derived objects; makefiles; view-private files, and (for builds performed with omake) non-MVFS objects that were explicitly declared as dependencies.
–typ/e { f | d | l } ...: Lists file system objects of a particular kind: files (f), directories (d), or links (l). The default value varies with the report style: normal and short listings (–short) default to f; long listings (–long) default to fdl. You may specify multiple kinds of objects by grouping them into a single argument; –type fd, for example.
–element_only: Lists versions of elements only, including checked-out versions. This option excludes from the listing derived objects (except DO versions), view-private files and directories, UNIX or Linux symbolic links, and non-MVFS objects.
–vie/w_only: Lists view-private objects only, including checked-out versions of elements. If you specify this option along with –element_only, the listing includes only checked-out versions of elements.
–cri/tical_only: Excludes from the listing any differences in objects marked as noncritical in the CR. Objects with that property typically have it because the user specified them as dependents of the .NO_DO_FOR_SIBLING special target in a clearmake or an omake makefile.
–nam/e tail-pattern: Considers the entry for a file system object only if its final pathname component matches the specified pattern. For a list of pattern-matching characters, see the wildcards_ccase reference page.

Controlling report appearance

Default: diffcr reports, in three sections, on MVFS objects, variables and options, and the build script. The report uses full path names, and it omits comments and directory versions.
–wd: Lists path names relative to the current working directory, rather than as full path names.
–nxn/ame: Lists simple path names for MVFS objects, rather than version-extended path names or DO IDs.
–fol/low: Lists the link targets only (that is, suppresses printing of the link text).
–l/ong: Expands the report to include the kinds of objects in the CR, and comments. For example, an object may be listed as a version, a directory version, or derived object (see ls –long for a complete list). Comments indicate whether an object is in a makefile, a referenced derived object, or a new derived object.
–s/hort: Restricts the report to file system objects only (omits header information, variables and options, and build scripts).

Specifying the derived objects

Default: None.
do-pname-1, do-pname-2: Standard path names, DO IDs, or both of two derived objects to be compared. Either or both can be a DO version.

Examples

The UNIX system and Linux examples in this section are written for use in csh. If you use another shell, you might 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 might 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 system and Linux shells or Windows command interpreter prompt, followed by the cleartool command. In cleartool interactive mode, cmd-context represents the interactive cleartool prompt.

Compare the CRs of two derived objects built at the name bgrs. Use lsdo to obtain the DO ID of the derived object that is not visible in the current dynamic view.

cmd-context lsdo -zero bgrs 
—12-11T15:24 "bgrs@@2007-12-11T15:24.1487"
—12-11T12:05 "bgrs@@2007-12-11T12:05.1256"

cmd-context diffcr –flat bgrs bgrs@@2007-12-11T12:05.1956 
< Reference Time 2007-12-11T.15:23:52, this audit started 2007-12-11T15:23:59
> Reference Time 2007-12-11T12:02:39, this audit started 2007-12-11T12:04:52
< View was oxygen:/usr/jones/views/main.vws 
		[uuid 66e68edc.471511cd.ac55.08:00:2b:33:ec:ab]
> View was oxygen:/usr/jones/views/r1_fix.vws 
		[uuid 8b468fd0.471511cd.aca5.08:00:2b:33:ec:ab]
----------------------------
----------------------------
MVFS objects:
----------------------------
< /vobs/docaux/bgr/linux_ppc64le/bgrs@@2007-12-11T15:24.1987
> /vobs/docaux/bgr/linux_ppc64le/bgrs@@2007-12-11T12:05.1956
----------------------------
< /vobs/docaux/bgr/linux_ppc64le/bugs.o@@2007-12-11T15:23.1981
> /vobs/docaux/bgr/linux_ppc64le/bugs.o@@2007-12-11T12:03.1902
----------------------------
< /vobs/docaux/bgr/linux_ppc64le/bugsched.o@@2007-12-11T15:23.1984
> /vobs/docaux/bgr/linux_ppc64le/bugsched.o@@2007-12-11T12:04.1953

The comparison shows that the builds used different versions of the object modules bugs.o and bugsched.o.

Compare the same two derived objects again, this time including the CRs of all subtargets.
cmd-context diffcr -flat bgrs.exe bgrs.exe@@11-Dec.12:05.1956
---------------------------- MVFS objects: ---------------------------- ---------------------------- < First seen in target "bugs.obj" < 1 \vob1\docaux\bgr\bugs.c@@\main\2 <2007-12-11T15:22:53> > First seen in target "bugs.obj" > 1 \vob1\docaux\bgr\bugs.c@@\main\1 <2006-12-19T11:49:54> ---------------------------- < First seen in target "bugsched.obj" < 1 \vob1\docaux\bgr\bugsched.c@@\main\2 <2007-12-11T15:23:04> > First seen in target "bugsched.obj" > 1 \vob1\docaux\bgr\bugsched.c@@\main\1 <2006-12-19T11:50:07> ---------------------------- < First seen in target "bgrs.exe" < 1 \vob1\docaux\bgr\bgrs.exe@@2007-12-11T15:24.1987 > First seen in target "bgrs.exe" > 1 \vob1\docaux\bgr\bgrs.exe@@2007-12-11T12:05.1956 ---------------------------- < First seen in target "bgrs.exe" < 2 \vob1\docaux\bgr\bugs.obj@@2007-12-11T15:23.1981 > First seen in target "bgrs.exe" > 2 \vob1\docaux\bgr\bugs.obj@@2007-12-11T12:03.1902 ---------------------------- < First seen in target "bgrs.exe" < 2 \vob1\docaux\bgr\bugsched.obj@@2007-12-11T15:23.1984 > First seen in target "bgrs.exe" > 2 \vob1\docaux\bgr\bugsched.obj@@2007-12-11T12:04.1953

The integer at the beginning of an entry indicates the number of times the object was referenced during the build. The first seen in target message indicates the first target rebuild in which the object was referenced.
For the same two derived objects as in the preceding examples, compare the file element versions used to build subtarget bugsched.o. Report the differences in short format.
cmd-context diffcr -short -select bugsched.o -type f -element_only \
bgrs bgrs@@2007-12-11T12:05.1956
---------------------------- < /vobs/docaux/bgr/bugsched.c@@/main/2 > /vobs/docaux/bgr/bugsched.c@@/main/1
Compare two builds of program main, listing only those entries that involve the files src/prog.c, include/prog.h, and bin/prog.o.
cmd-context diffcr -recurse -name 'prog.[cho]' main1 main2
Compare two builds of program main, listing only those entries that involve the file src\prog.c
cmd-context diffcr -recurse -name prog.c main1 main2