ClearCase windows Certification sample Questions

Question: 1
The semi-live backup strategy minimizes VOB downtime by locking the VOB only long enough to
copy the database subdirectory of the VOB's physical storage area.
A. True
B. False
Answer: A
Question: 2
Which of the following actions can you complete using the clearicense command? (Select all that
apply)
A. Enable license auditing
B. Report on current license use
C. Release a license
D. Add new license codes
E. Establish priority user licenses.
Answer: A, B, C
Question: 3
To access views and VOB's from a region they must have a tag in that region.
A. True
B. False
Answer: A
Question: 4
Which command lists all view-tags in the current region?
A. dir of the MVFS drive
B. cleartool setview -all
C. cleartool lsview
D. cleartool is of the MVFS drive
Answer: C
Question: 5
The storage directories of the dynamic view and snapshot view contain the same subdirectories.
A. True
B. False
Answer: A
Question: 6
Which of the following objects are viible in the ClearCase Explorer display? (Select all that apply)
A. Hyperlink
B. View-private file
C. Hard link
D. DIRECTORY ELEMENT
E. Symbolic link
Exam Name: ClearCase for Windows
Exam Type IBM
Exam Code: 000-630 Total Questions: 163
Answer: A, B, C
Question: 7
The default behavior of the clearesport_rcs and clearexport_pvcs commands is to translate
symbols into labels or branches as appropriate.
A. True
B. False
Answer: A
Question: 8
Entering a ClearCase command causes a trigger to fire. The trigger's associated script
references a comment linked with that command. Which environment variable does the script use
to identify the comment entered with the ClearCase command?
A. CLEARCASE_CMNT_PN
B. CLEARCASE_CQ
C. CLEARCASE_CFILE
D. CLEARCASE_DESCRIP
E. CLEARCASE_COMMENT
Answer: E
Question: 9
The VOB semi-live backup strategy is only available for version 3.2.1 and higher VOB's
A. True
B. False
Answer: B
Question: 10
On the host where the view storage directory resides, an asterisk ( * ) appears to the left of a view
- tag in Isview output. What does the asterisk mean? (Select all that apply)
A. View storage directory resides on the local host.
B. View server process is running
C. View is currently in use
D. View is visible on the MVFS drive
Answer: B, D
Question: 11
A host's MVFS (M:) drive has a subdirectory for every active dynamic view on the host.
Under which of the following conditions does a dynamic view become active? (Slect all that apply)
A. View server process is started on that host
B. Cleartool startview comman is executed on the host
C. View is set on that host ith cleartool setview
D. ALDB server process is started on that host
Answer: A, B
Exam Name: ClearCase for Windows
Exam Type IBM
Exam Code: 000-630 Total Questions: 163
Question: 12
You must run the leartool protectvob command when the VOB is unmounted on all hosts.
A. True
B. False
Answer: B
Question: 13
You can restart the cleartool relocate command for all phases except if it has halted during the
final phase (removal of source elements).
A. True
B. False
Answer: A
Question: 14
Which of the following commands must you issue from the command prompt to shut down
ClearCase? (Select all that apply)
A. net stop vob_server
B. net stop lockmgr
C. net stop clearcase_albd
D. net stop mvfs
E. net stop albd
Answer: A, B, C
Question: 15
It is essential to back up a view because objects in a view's storage directory cannot be accessed
by other view?
A. True
B. False
Answer: A
Question: 16
What happens to non-versioned derived objects after cleartool relocate executes?
A. They are relocated to the target VOB.
B. They are not relocated.
C. They are deleted.
D. They are invalid in the originating VOB.
Answer: C
Question: 17
The cleartool catcs command will display the configuration record of a built object.
A. True
B. False
Answer: B
Exam Name: ClearCase for Windows
Exam Type IBM
Exam Code: 000-630 Total Questions: 163
Question: 18
Unprivilieged ClearCase users have read-only access to the ClearCase Properties applet.
A. True
B. False
Answer: B
Question: 19
It is necessary to reboot the computer after uninstalling ClearCase.
A. TRUE
B. False
Answer: A
Question: 20
The ClearCase Server Storage Configuration Wizard sets up view and VOB share directories,
which are suggested to clients when they create the respective dta structures via the Create VOB
or Create View Wizard.
A. True
B. False
Answer: A
Question: 21
Which host is executing the view_server process for a dynamic view?
A. The host that first activates the view
B. The host wher view_private files are loaded
C. The same host as the vob_server process.
D. The host where the view storage directory physically resides.
Answer: D
Question: 22
Which of the following options of the cleartool subcommand getlog returns a listing of all log files
on thee current host? (Select all that apply)
A. getlog - long
B. getlog - inquire
C. getlog - isall
D. getlog - graphical
Answer: B, D
Question: 23
The command recoverview calls cleartool reformatview.
A. True
B. False
Answer: A

SOA Fundamentals IBM Certification sample

Question: 1
Which business factor least promotes a trend towards SOA?
A - The forces of change
B - Enterprise reconstruction
C - Industry deconstruction
D - Organizational stability
Answer: D
Question: 2
Which two are barriers to the adoption of SOA?
A - An existing component Infrastructure
B - A deliberate, well-conceived path from the “as-is” to the “to-be” goal
C - A failure to collaborate across product units or divisions
D - Time spent in face-to-face customer meetings
E - The corporate tendency to just male it work
Answer: C, E
Question: 3
Which SOA entry point most accurately matches the following sentence? “Start by modeling an
underperforming process, remove bottlenecks, then simulate and deploy the optimized process.”
A - People
B - Process
C - Connectivity
D - Information
E - Reuse
Answer: B
Question: 4
Which SOA implementation change needs proper versioning of services?
A - New operations to existing service
B - Relocation of UDDI registries
C - Changes to service implementation
D - Changes to transport implementation
Answer: A
Question: 5
What is the most important business and technical benefit to an SOA?
A - Standardized integration of diverse and complex business systems
B - Ability to respond quickly to change and gain a competitive advantage
C - Justify the cost of investment in IT resources
D - True real-time performance of critical business applications
E - Loyal customers and improved end-user experience
Answer: B
Question: 6
Exam Name: SOA Fundamentals
Exam Type: IBM
Exam Code: 000-664 Total Questions: 54
Which is a true factor that poses a challenge to SOA adoption by organizations?
A - Stable and consistent technical standards
B - Co-location of service components
C - Universal inter-operability amongst different platforms
D - Defining services with appropriate granularity
Answer: D
Question: 7
Which three are benefits that SOA can provide to the IT community?
A - Homogenizes the IT environment
B - Promotes reuse of services
C - Promotes flexible solutions
D - Regulates the products that can be used in the IT environment
E - Justifies investment in IT more clearly
F - Increases traffic and throughput of business applications
Answer: B, C, E
Question: 8
IBM, in partnership with Mercer Management Consulting, has identified three core businesscentric
SOA starting points and two IT-centric starting points. What are two IT-centric starting
points from the answer choices?
A - People
B - Process
C - Connectivity
D - Policy
E - Reuse
Answer: C, E
Question: 9
Which two people or technology factors could have a negative impact on a companys readiness
for SOA?
A - An understanding that SOA requires a paradigm shift towards more flexible business models
B - Resistance to change in the organization
C - Empowerment of an SOA governance body
D - Support of senior executives
E - A vision of SOA that is not balanced with the delivery capabilities of the IT department
Answer: B, E
Question: 10
Which four are barriers to the adoption of SOA?
A - Seeking customer input when inventing new products
B - Obsession with time to market
C - A risk-taking management style
D - Organizational silos
E - Unskilled partners
F - A limited pool of local talent
Exam Name: SOA Fundamentals
Exam Type: IBM
Exam Code: 000-664 Total Questions: 54
G - Focusing on new market opportunities
Answer: B, D, E, F
Question: 11
Which factor is the least likely key business driver in deciding to adopt an SOA?
A - The existing technology represents an organic infrastructure that is simply too expensive or
complex to maintain.
B - The existing system is exhibited proudly as evidence that the company is at the forefront of
data-processing technology.
C - The existing system fails to offer the capabilities that the myriad of new business challenges
require.
D - There are massive cultural changes occurring in business mergers, acquisitions, downsizing,
and upsizing.
Answer: B
Question: 12
Which two people or technology factors have a positive impact on a companys readiness for
SOA?
A - The clear division between the language used by the business operations community and the
technical jargon of the IT community
B - Focusing on the technical issues and not considering the organizational issues
C - Finding an enterprise approach that allows business leaders and IT to meet in the middle
D - Unlocking new ways to address the issue of business-driven software changes and
implementation
E - An existing investment in rich-feature software technologies
Answer: C, D
Question: 13
An online music store lets customers listen to the first part of songs for an album. If they buy the
song, it is downloaded to their computer. Which three are the best services?
A - Open the music store
B - View songs on an album
C - Listen to a song clip
D - Buy a song
E - Listen to an album
F - Print a receipt
Answer: B, C, D
Question: 14
Which standard specifies how integrity and confidentiality can be enforced on Web services?
A - WS-Security
B - WS-Encryption
C - WSDL
D - WSRP
Answer: A

ClearCase Unix certification question sample

Question: 1
Which of the following actions can you complete using the clearlicense command? (Select all that
apply)
A. Enable license auditing
B. Release a license
C. Report on current license use
D. Add new license Codes
E. Grant licenses to priority users
Answer: B, C
Question: 2
The cleartool casts command will display the configuration record of a build object.
A. True
B. False
Answer: B
Question: 3
Which command allow a user to obtain command syntax help from the command prompt? (Select
all that apply)
A. cleartool subcommand -help
B. cleartool -help subcommand
C. cleartool help subcommand
D. cleartool subcommand help
Answer: A, C
Question: 4
What is the length of the default timeout period on a ClearCase license?
A. 15 minutes
B. 30 minutes
C. 60 minutes
D. 120 minutes
Answer: C
Question: 5
ClearCase for UNIX supports remote storage pools for derived object and cleartext pools.
A. True
B. False
Answer: A
Question: 6
What cleartool command do you use to list the derived objects created by clearmake?
A. diffcr
B. catcs
C. catcr -flat
Exam Name: ClearCase for UNIX
Exam Type IBM
Exam Code: 000-631 Total Questions: 81
D. lsdo
E. ls - la
Answer: D
Question: 7
Can a snapshot view's view.dat file be moved to a network server host without ill effects?
A. Yes
B. No
Answer: B
Question: 8
A user can change from write access to read-only access on a checked-out version by issuing the
cleartool protect ugo.w command.
A. True
B. False
Answer: B
Question: 9
How does a derived object inherit its pool assignment?
A. From the file element that created the first-level target
B. From the directory where the executable is versioned
C. From the directory where the target was built
D. From the derived object assignment tables
Answer: C
Question: 10
Which operation (s) require the registry password? (Select all that apply)
A. Change the registry password
B. Change a private VOB to a public VOB
C. Remove a public VOB
D. Create a public VOB
Answer: B, D
Question: 11
What is the effect of using cleartool chpool on a file element? (Select all that apply)
A. For cleatext pools, future versions will be put in the new pool.
B. For source pools, future versions will be put in the new pool.
C. For cleartext pools, all versions are moved to the new pool.
D. For source pools, all versions are moved to the new pool.
Answer: A, D
Question: 12
You want to get detailed information about a build. What do you examine?
Exam Name: ClearCase for UNIX
Exam Type IBM
Exam Code: 000-631 Total Questions: 81
A. Configuration records
B. Derived objects
C. Makefile
D. View's lo files
E. Configuration specification
Answer: A
Question: 13
"src" is a subdirectory of your current directory. What actions occur when you enter the
command:
clearexport_ffile src?
A. All files are processed, sub-directories are processed recursively, symbolic links are
processed and the data written to a file called cvt_data.
B. All files and sub-directories in the src directory except hidden files are exported, and output
written to a file called cvt_data
C. All files and subdirectory names in the src directory are exported, and the data written to a file
called cvt_data.
D. All files and onlyt subdirectory names in the src directory are exported, and the data written to
a file cvt_data.
Answer: D
Question: 14
Which of the following element types does ClearCase store as interleaved deltas? (Select all that
apply)
A. text_file
B. html
C. ms_word
D. xml
Answer: A, B, D
Question: 15
The commands clearexport_ccase and clearimport copy elements from one VOB to another.
A. True
B. False
Answer: A
Question: 16
Which host is executing the view_server process for a snapshot view?
A. The host where the view storage directory resides
B. The host where view_private files are loaded
C. The same host as the vob_server process
D. The host that first activates the view
Answer: A
Question: 17
Any member of any group can change the config spec of a view.
Exam Name: ClearCase for UNIX
Exam Type IBM
Exam Code: 000-631 Total Questions: 81
A. True
B. False
Answer: B
Question: 18
Only the owner of a ClearCase object can transfer ownership of that object.
A. True
B. False
Answer: B
Question: 19
The ClearCase network release area must be on a Clear Case installed host.
A. True
B. False
Answer: B
Question: 20
A user may access VOB data either by makin the VOB -tag or the VOB storage directory the
current directory.
A. True
B. False
Answer: B
Question: 21
A user can specify a VOB to mount with either the VOB-tag or the VOB storage pathname.
A. True
B. False
Answer: B
Question: 22
What is the purpose of the cleartool protectvob command? (Select all that apply)
A. Change the ownership of VOB
B. Change the primary group of a VOB
C. List the owner and groups for a VOB
D. Add groups to a newly created VOB
E. Remove the primary group Of a VOB
Answer: B

Clear case with Unix

UNIX admin questions

1.1.1 How to remove (specify) a file with a name beginning in "-"?

Say "./-filename".

1.1.2 setview in scripts doesn't work

Running "setview" without the "-exec" flag starts a new shell.

Generally, using "setview -exec" is a deprecated way of doing things. It will not work on NT, and it will not work in snapshot views. Instead, one should use view extended path names.

When writing scripts, it is a good idea to normalize path names to the view root, which can be obtained by running "cleartool pwv -root". Note that this returns an empty string when run in a setview context. Therefore, you can safely append an absolute pathname beginning wiht the vob tag to the value returned by "cleartool pwv -root".

1.1.3 Get "Event not found." error when running the cleartool find command. (Frederick Sena )

For example:

 % ct find . -version "!version(/main/0)" -print

This is a csh'ism. The "!" is interpreted as an event reference, and this is done prior to resolving the quotes. Use "\!" as in:

 % ct find . -version "\!version(/main/0)" -print

1.1.4 When I try to unmount a vob, I get a "Device busy" error and the vob does not unmount. (Frederick Sena )

Make sure no process has its working directory set to a path beginning with the vob's vob tag. One can use fuser(1) to determine which processes are using that file system.

It has been observed that this isn't enough in some cases. In extreme cases, only a reboot will clear out the locks.

1.1.5 In which order should I upgrade my servers and clients?

Servers first, clients later. Always refer to the release notes for details on any particular upgrade.

1.1.6 When shutting down Clearcase, I get "device busy"...

See 1.1.4.

1.1.7 How can I support more users with my limited set of licenses?

First, start by monitoring your license usage over the day. There are some nice packages that allow you to do this, For example Ed Finch's ClGraph.

The next thing is to reduce the license timeout to the minimum allowed: 30 minutes. Do this by adding a line saying: -timeout 30 into your /var/adm/atria/license.db file. You may also want to give a list of priority users by adding lines saying: -user userid.

If you still run out of licenses (and you can't afford to buy more), you can ask people to say clearlicense -release, but keep in mind you can only do this a limited number of times per day (approx. twice the number of licenses).

Touching the /var/adm/atria/license.db file releases all licenses at once, but again this can only be done 12 times per day. I use a crontab script similar to the one below, touching the file at a frequency that roughly matches my usage pattern:

5 9,10,11,1,2,3,4,5,6 * * * /bin/touch /var/adm/atria/license.db

Yet another way to reduce license usage is to encourage developers to use snapshot views and ensure that your change process knows how to deal with snapshot views, as there are a couple of pitfalls. Developers usually need little encouragement, as they will gladly sacrifice dynamic views for faster build performance, especially on NT systems.

1.2 Elements

1.2.1 How to undo a mkelem if rmelem is disabled?

Most sites disable the rmelem command, therefore you cannot undo a mkelem directly. Instead, you should use the rmname (rm for short) command.

Suppose, for example, you accidentally created the subdir element as a file element instead of a directory element. Use this procedure to correct the problem:

% ct mkelem subdir   <== error!

Created element "subdir" (type "compressed_file").

Checked out "subdir" from version "/main/0".



% ct ci -identical -nc subdir

Checked in "subdir".



% ct rm subdir

cleartool: Warning: Object "subdir" no longer referenced.

cleartool: Warning: Moving object to vob lost+found directory as

                   "subdir.9e881d0d390711d5b3ee000180a933fe".

Removed "subdir".



% ct mkdir subdir

Created directory element "subdir".

Checked out "subdir" from version "/main/0".



%

The checkin is mainly for cosmetic reasons and to avoid confusion if this procedure is used in a snapshot view. In the end, the element isn't removed but just relocated into the trash bin. The ClearCase administrator will empty out the trash once in a while.

This procedure will not work as described if you don't notice the error immediatly and check in the containing directory. If you later check out the directory and remove the element, you will notice that it doesn't get relocated into lost+found, since the previous version of the directory still has a reference to that element. If you then attempt to create a directory element with the same name, the evil twin trigger will get in your way. You can fool the trigger, though, by first creating a directory element with a different name and then renaming it using the ct mv command.

1.2.2 How to undo an rmname?

The important thing to remember is that renames, additions and removals of elements from a directory are all harmless and recoverable, so don't panic!

It helps to visualize additions, removals and renames as editing the containing directory. It's very much like adding, removing or changing lines in a file, and the recovery procedures are similar.

The easiest thing to do is to simply cancel the checkout of the directory. This will restore the previous version of the directory, and the removed elements will reappear, as if by magic:

% ct co -nc .

Checked out "." from version "/main/234".



% ct rm file  <=== OOOPS!!

Removed "file".



% ct unco .

Checkout cancelled for ".".



% ls file

file



%

If you don't notice the error immediately and have already checked in your directory, you can take advantage of the evil twin trigger and allow it to help you. Simply attempt to re-mkelem the deleted element and follow the instructions:

% ct co -nc .

Checked out "." from version "/main/234".



% ct mkelem file

ERROR:  An element named "file" already exists in

       in some other version of ".":



Instead of creating a new element, you probably want to

create a hard link to the existing element, like so:



cleartool ln .@@/main/LATEST/file .



% ct ln .@@/main/LATEST/file .

Link created: "./file".



%

In general, directories don't contain elements but contain named links to elements. Removing an element doesn't destroy the element, it just removes the link. It is therefore almost trivial to resurrect a removed element.

One consequence is that removing directories and removing files are really the same operation, and the recovery procedure is identical. In particular, if you accidentally removed a whole tree, you only need to recreate the link to the topmost directory of that tree.

1.2.3 I do a findmerge or a checkout and see: "Not a VOB object", but I know that the file is a VOB object.

You are probably dealing with an eclipsed file. Run "cleartool ls" on the file, and if you see "[eclipsed]", simply rename the file out of the way using a plain ordinary "mv" and retry the operation.

The most common way this happens is when developers copy files from other views. Don't do that. Merge the containing directories instead.

1.2.4 How can I locate Hard Links?

A more precise formulation would be: "How do I locate elements that are linked into two or more different directory elements?". There is no really good method to do this except by exhaustive search, for example by using this technique:

Run this command:

 % find . -print | record_inodes

where record_inodes is this little perl script:

#!/bin/perl



%links = ();  # hash indexed by inodes containing an array of

             # directory locations



%twice = ();  # hash indexed by those inodes referenced by two

             # or more directories

while (<>) {

 chomp;

 next if $_ eq '.';           # skip top level

 next if -l $_;               # skip over symlinks



 ($dir = $_) =~ s,/[^/]*$,,;  # determine directory of element



 # get inode of version 0, if it exists. If not, use

 # just stat the file itself. This way, this script can

 # be used outside of clearcase too.

 $zero_version = $_.'@@/main/0';

 ($dev, $inode) = (-e $zero_version

                   ? stat($zero_version)

                   : stat($_));



 if (exists($links{$inode})) {

   # register new location and register inode as "interesting"

   push(@{$links{$inode}}, $_);

   $twice{$inode}++;

 } else {

   # initialize array of locations

   $links{$inode} = [ $_ ];

 }

}



if (%twice) {

 print "------------------------------------------------------------\n";

 for $inode (keys(%twice)) {

   print(map("  $_\n", @{$links{$inode}}));

   print "------------------------------------------------------------\n";

 }

} else {

 print "No element linked to multiple directories found.\n";

}

1.2.5 RCS Keyword expansion?

This is probably the single most often asked question. The simple answer is that ClearCase doesn't support RCS keyword expansion, mainly for one reason: it would break merges.

Since two different versions would always have a different RCS keyword expansion at the same location within the file, any merge between those two versions would invariably cause a conflict that couldn't be resolved automatically.

In general, "inband info" (i.e. storing information about an object within an object) is a bad idea, since care must be taken not to confuse any random string with the actual metadata. A vivid demonstration of the danger can be found when attempting to check into RCS files that explain how RCS keywords work.

Instead of storing metadata within the data, one should take advantage of ClearCase's extensive metadata types (attributes, hyperlinks, comments etc...).

The obvious follow-up question then is: "How do I access the metadata when I can't connect to ClearCase?" There are really two cases here:

• Version info on the production system;
• Version info in an offline development source tree, for example a disconnected snapshot view.

The correct solution to the first case is to insert the RCS keywords at build or packaging time. There are tools to insert keywords into binaries, for example the contributed package T0039 (ccwhat).

The second case is the best argument for implementing RCS keywords, and if it's truely important to your environment, read on...

There are ways to make RCS keywords work within ClearCase, but they are by no means trivial. The best method so far is to use the contributed package T0027, which contains both a trigger and a type manager. The trigger does the actual work of substituting RCS keywords, and the type manager avoids the merge conflicts by interposing itself between the file and the real type manager, removing all RCS keywords.

Note that even with this solution, your branching strategy should be set up to deal with the case described in the diagram on the right. Assume that the blue developer delivers a change (1) of some file into the red delivery branch. He then never touches that file again. The green developer then makes another change and delivers it (2). The blue developer, having done changes in some other files wants to sync up and executes a findmerge from the red branch, which will cause green's change to be merged over as a copy merge (3). Now, the blue developer wants to deliver his other changes, but since the merge in (3) caused the RCS keywords to change, findmerge will think that blue modified the file even though he didn't and cause (4) to happen, which is somewhat bewildering.

The reason this happens is because the findmerge algorithm has a case where the actual file content is compared. Unfortunately, findmerge does not use the type manager's compare function, but something hard coded and will think the files are different even though the only difference is in the keywords.

There are two possible workarounds:

• delete or rename the development branches after delivery. This is a good thing to do in general, since it will keep the version tree looking clean, especially if the development branch name is to be re-used for the next change;
• have the RCS keywords pre-checkin trigger look for a merge hyperlink, test if the merge was a copy merge and if yes, don't modify the keywords.

1.2.6 How to perform mass checkouts?

On UNIX:

 % cleartool find path -print | awk '{print "co -nc \""$0"\""}' | cleartool

Most often, this is done in the context of upgrading third party software or doing some other form of mass checkin. Recently, Rational came up with clearfsimport, a tool that will apparently do the right thing. Stay tuned...

1.2.7 How to perform mass checkins?

On Unix:

 % cleartool lsco -s -cview -me -avobs -fmt 'ci -nc "%n"\n' | cleartool

The commands above will fail if no changes have been made. You can either insert the -identical flag or re-run the above once more, this time canclling the checkouts with unco -rm.

Most often, this is done in the context of upgrading third party software or doing some other form of mass checkin. Recently, Rational came up with clearfsimport, a tool that will apparently do the right thing. Stay tuned...

1.2.8 what is an evil twin?

An evil twin is two links with the same name, each pointing to a different element, in two different versions of the same directory element.

The reason they are evil is because they create the appearance of a directory containing the same file on two different branches, when in fact they contain two different files with the same name. If this situation isn't detected, then one can very well end up with two change histories of something that everybody thought of being the same file, only to get a rude surprise at merge time. There is essentially no good way to merge the two change histories.

Evil twins get created when two developers concurrently add the same file to source control without coordination, or if one developer copies files from another developer's view and puts those files under source control.

Copying files around should be discouraged, but the best way to avoid evil twins is to create a pre-mkelem trigger that will search through some or all versions of the directory containing the new element, verifying that no link with the same name exists.

The following perl code implements this trigger and prints out a warning together with the suggested link command that will link the existing element into the version of the directory where the newly created element would have ended uup.

The trigger will also do a sanity check on the file name itself, catching most unintentional element creation attempts.

The trigger relies on the excellent ClearCase::ClearPrompt and ClearCase::Argv modules, available at a CPAN site near you.

#!/bin/perl



use ClearCase::ClearPrompt qw(:all);

use ClearCase::Argv qw(ctsystem ctexec ctqx);



# Deal with the possibility of no display on Unix.

BEGIN { $ENV{ATRIA_FORCE_GUI} = $^O =~ /win32/i ? 1 : $ENV{DISPLAY} }



#--------------------------------------------------------------------

# Debugging aid. Overloading the semantics of the standard

# CLEARCASE_TRACE_TRIGGERS EV: if it's set to -2 we dump

# the runtime environment into a file in the current dir.

#--------------------------------------------------------------------

if (int($ENV{CLEARCASE_TRACE_TRIGGERS}) < 0 &&

		  $ENV{CLEARCASE_TRACE_TRIGGERS} & 0x2) {

  open (EV, ">chk_dup_elems_env.txt");

  print EV "$x=$y\n" while (($x,$y) = each %ENV);

  close EV;

}



#--------------------------------------------------------------------

# See if the user wants to suppress this trigger's actions:

#--------------------------------------------------------------------

exit 0 if $ENV{CCASE_NO_CHK_DUP_ELEMS};



#--------------------------------------------------------------------

# Figure out the null device.

#--------------------------------------------------------------------

$null = $^O =~ /win32/i ? 'NUL' : '/dev/null';



#--------------------------------------------------------------------

# Catch some really bad pathnames - we can't catch everything, but

# let's try to be good.

#--------------------------------------------------------------------



$elname = $ENV{CLEARCASE_PN};

$elname =~ s,\\,/,g if $ENV{OS} eq 'Windows_NT';

$elname =~ s,/*$,,;



if ($elname =~ /[\"\(\)\{\}\[\]\\\'\^~\!\#]/ || # illegal characters;

   $elname =~ /\s+\// ||                       # leading or trailing

   $elname =~ /\/\s+/ ||                       # spaces at slashes,

   $elname =~ /^\s+/ ||                        # or at the beginning

   $elname =~ /\s+$/ ||                        # or at the end;

   $elname =~ /\.$/)                           # trailing dot.

{

   # substitute offenders with X

   $elname =~ s/[\"\(\)\{\}\[\]\\\'\^~\!\#]/X/g;

   $elname =~ s/\s+\//X\// ||

   $elname =~ s/\/\s+/\/X/ ||

   $elname =~ s/^\s+/X/;

   $elname =~ s/\s+$/X/;



   $prompt = <

ERROR:  The new element name contains characters

       that will cause problems in many scripts.



Please do not use quoting characters within filenames.

Also, please do not end a filename with a dot, as NT

cannot deal with this. Finally, do not use leading

or trailing spaces. Your name was (X = illegal):



  $elname



EOT

   if ($ENV{CCASE_NO_CLEARPROMPT}) {

     print STDERR $prompt;

   } else {

     clearprompt(qw(proceed -type error

                            -default abort

                            -mask abort

                            -promt),

		  $prompt);

   }

   exit 1;

}



$dirname =  $elname;

$elname  =~ s,.*/,,;

$dirname =~ s,[^/]*$,.,;



@vlist = grep(!m,/\d+$,, ctqx(qw(lsvtree -short), $dirname));



# OK, now look in each branch of this directory for the file element to

# be created; display info on error.



$found = '';

%seen = ();

unless (-d $dirname.$ENV{CLEARCASE_XN_SFX}.'/main') {

 # snapshot view

SNAP_VERSION:

 foreach (@vlist) {

   chomp;

   if (m,/CHECKEDOUT$,) {

     # Multiple (unreserved) checkouts appear multiple times

     next SNAP_VERSION if $seen{$_};

     $seen{$_}++;

     ($xpn = $_) =~ s,CHECKEDOUT$,,;

     # unreserved checkouts - there can be several...

     foreach (grep(m,/CHECKEDOUT\.\d+$, ,

              ctqx(qw(ls -short), $xpn))) {

	chomp;

	unless (ctsystem({stdout => 0, stderr => 0},

                        qw(ls -d), "$_/$elname")) {

	  $found = "$_/$elname";

	  last SNAP_VERSION;

	}

     }

   } else {

     # only check the LATEST in a non-checkout branch

     unless (ctsystem({stdout => 0, stderr => 0},

                      qw(ls -d), "$_/LATEST/$elname")) {

	$found = "$_/LATEST/$elname";

	last SNAP_VERSION;

     }

   }

 }

} else {

 # dynamic view

DYN_VERSION:

 foreach (@vlist) {

   chomp;

   if (m,/CHECKEDOUT$,) {

     # Multiple (unreserved) checkouts appear multiple times

     next DYN_VERSION if $seen{$_};

     $seen{$_}++;

     ($xpn = $_) =~ s,CHECKEDOUT$,,;

     # unreserved checkouts - there can be several...

     foreach (grep(m,/CHECKEDOUT\.\d+$, ,

                   ctqx(qw(ls -short), $xpn))) {

	chomp;

	if (-d "$_/$elname") {

	  $found = "$_/$elname";

	  last DYN_VERSION;

	}

     }

   } else {

     # only check the LATEST in a non-checkout branch

     if (-d "$_/LATEST/$elname") {

	$found = "$_/LATEST/$elname";

	last DYN_VERSION;

     }

   }

 }

}



# Nothing; go ahead.

#

exit 0 unless $found;



$prompt = <

ERROR:  An element named "$elname" already exists in

       in some other version of "$dirname":



Instead of creating a new element, you probably want to

create a hard link to the existing element, like so:



% cleartool ln $found .



EOT



if ($ENV{CCASE_NO_CLEARPROMPT}) {

 print STDERR $prompt;

} else {

 clearprompt(qw(proceed -type error

                        -default abort

                        -mask abort

                        -prompt),

	      $prompt);

}

exit 1;

1.2.9 How can I see who changed what parts of a file and when?

Look up the "cleartool annotate" command.

1.2.10 Uncheckout leaves a zero version on branch; is this bad?

I consider it a nuisance. One common development strategy is for every developer to create their own development branch by using a view with a config spec similar to this one:

element * CHECKEDOUT

element * .../mybranch/LATEST

element * BASELINE -mkbranch mybranch

element * /main/0 -mkbranch mybranch

Note that whenever a developer starts working on some file he hasn't touched, a branch gets created at that point. As work progresses, more and more elements will have a "mybranch" branch.

Once in a while, the BASELINE label gets moved to the newest approved base line, and developers are encouraged to rebase via a merge. The merge will do something for every element that has a "mybranch" branch and for which the version that BASELINE selects changed since the branch was made.

If one leaves zero versions on the "mybranch" branch behind, then this will cause copy merges, which won't affect the logical concistency of your view of the source tree, but will affect performance. Besides, zero versions just look sloppy.

Most sites add a post-rmbranch and post-unco trigger to remove the dangeling branch with only a zero version. The following code implements this trigger. Paul D. Smith wrote this trigger, and I added some code to deal with snapshot view weirdness:

#!/bin/perl



#--------------------------------------------------------------------

# Nothing special needed Perl-wise - allow Rational Perl to be used

#--------------------------------------------------------------------

require 5.001;



#--------------------------------------------------------------------

# Debugging aid. Overloading the semantics of the standard

# CLEARCASE_TRACE_TRIGGERS EV: if it's set to -2 we dump

# the runtime environment into a file in the current dir.

#--------------------------------------------------------------------

if (int($ENV{CLEARCASE_TRACE_TRIGGERS}) < 0 &&

		  $ENV{CLEARCASE_TRACE_TRIGGERS} & 0x2) {

  open (EV, ">rm_empty_branch.txt");

  print EV "$x=$y\n" while (($x,$y) = each %ENV);

  close EV;

}



#--------------------------------------------------------------------

# See if the user wants to suppress this trigger's actions:

#--------------------------------------------------------------------

exit 0 if $ENV{CCASE_NO_RM_EMPTY_BRANCH};



#--------------------------------------------------------------------

# Use safest quoting possible - java creates files with $ in

# them, so I can't just universally use "

#--------------------------------------------------------------------

$q = ($ENV{OS} eq "Windows_NT" ? '"' : "'");



# Remove empty branches: if a branch has no elements (except 0 of

# course) after an uncheckout or rmver, or the parent of a

# just-rmbranched branch is now empty, remove it.

#

# If the branch in question is /main, don't do anything (another option

# would be to rmelem the entire element, but that seems like a very bad

# idea to me).

#

# Install like this:

#

#   ct mktrtype -element -global -postop uncheckout,rmver,rmbranch \

#       -c "Remove empty branches after uncheckout, rmver, or rmbranch." \

#       -exec /TRIGGERS/rm_empty_branch RM_EMPTY_BRANCH

#

# CAVEATS:

#   - Ignores attributes!

#   - Won't remove branches where the 0th element is labeled.

#   - Will fail if any branch names contain spaces.

#   - May fail if any branch or label is named ".*" or "*" exactly.

#

# CREATED BY:

#   Paul D. Smith 

#



$xname = $ENV{CLEARCASE_XPN};

$xname =~ s,\\,/,g if $ENV{OS} eq 'Windows_NT';



# For uncheckout commands, if the version isn't 0 we can punt early

#

exit 0 if ($ENV{CLEARCASE_OP_KIND} eq 'uncheckout' &&

	   $xname !~ m,/0$,);



# Don't try to remove the /main branch

#

($branch = $xname) =~ s,/[^/]*$,,;

exit 0 if $branch =~ m,\@\@/main$,;



# Check if there are other versions, other branches, labels, or checked

# out versions on this branch: if so, don't do anything.

#

if (opendir(D, $branch)) {

 # this opendir succeeds only in a dynamic view

 @other_stuff = readdir(D);

 closedir(D);



 # in an empty branch, there are four thingies:

 # ".", "..", "0" and "LATEST". If there are more, then

 # it isn't an empty branch.

 exit 0 if (scalar(@other_stuff) != 4);

} else {

 # version extended name space not available implies

 # we're in a snapshot view, and we will have to work

 # a little harder here...

 ($pname, $brpath) = split($ENV{CLEARCASE_XN_SFX}, $branch);

 # an rmbranch will not reload the element...

 system("cleartool update -log /dev/null $q$pname$q")

   if ($ENV{CLEARCASE_OP_KIND} eq 'rmbranch');

 @vtree = `cleartool lsvtree -branch $brpath $q$pname$q`;

 chomp($latest = pop(@vtree));

 $latest =~ tr,\\,/, if $ENV{OS} eq 'Windows_NT';

 exit 0 unless $latest =~ m,$brpath/0$,;

}



# Remove it!

system("cleartool rmbranch -force -nc $q$branch$q");



exit 0;

1.2.11 I can see a file on one branch, but I can't see it on another branch for the same directory. How can I get the file to appear on the other branch? (Frederick Sena )

You use the cleartool ln command. See 1.2.14 for figuring out how to specify the invisible file as an argument to that command.

1.2.12 When I do cleartool ls, it says "[eclipsed]". What does "eclipsed" mean?

This occurs if you have a view private element of the same name as an element in the CC structure. You probably want to see the checked-in element, but what you see is your own copy. This usually happens by copying a file into a folder where such a versioned element exists (in a normal file system, this would be overwritting the original file), or when you copy a whole subtree that someone else already put under version control, and later update your config spec to show those files.

1.2.13 How to check in a file that hasn't change (or is empty) (Bygland, Brian )

Consider simply cancelling the checkout, but be aware that if the checkout was the result of a merge, cancelling the checkout will result in the merge arrow disappearing, forcing you to redo the merge next time. In this case, using the -identical flag of the checkin command may be preferable.

Answered by cg@miaow.com

1.2.14 How to see a file that your view / config spec can't see (Bygland, Brian )

The reason why you're not seeing the file is that the version of the directory selected by your view doesn't have a link to that file. Therefore the solution is to figure out which version of that directory element has the link.

The easiest way to access such a file is to use a different view, namely, one that selects the appropriate version of the directory. Even if you are set to some view that doesn't, you can use the so-called view extended path to refer to the other view. On UNIX, this is done be prepending /view/viewtag to the full pathname.

In some situations, it may not be convenient or safe to use view extended paths. One problem is that while you are using a view extended path, someone else may be changing the config spec of that view. For logging purposes in particular, you are better off storing the object id of the element and letting ClearCase tell you a patnname that is valid in your view. In other words, first take a view that selects your invisible file and run this:

% cleartool setview otherview



% cleartool describe -fmt '%On\n' path/to/invisible/file@@

03fcf938.39c011d5.b891.00:01:80:ab:ed:ac

Note that the final @@ at the end of the path tells ClearCase that you are interested in the element's object id. Omitting the final @@ would give you the version's object id, whih may or may not be what you need. Now to retrieve a pathname valid in your view, do this:

% cleartool setview myview



% cleartool describe -fmt '%p\n' oid:03fcf938.39c011d5.b891.00:01:80:ab:ed:ac

/vob/somevobtag/path@@/main/2/to/main/1/invisible/main/3/file@@

Note how we enter version extended name space (or history mode on NT) very early in the path. This is natural, since our premise is that the file isn't visible in our current view. These paths can become quite long, easily exploding NT's stupid limit on path name length or command line length if you every try to use that pathname for some command.

Note that this technique is very useful for tracking down relocations. If in the example above the file was relocated to some unknown but visibile location, Clearcase would have shown that location instead. ClearCase is amazingly smart in figuring out the shortest possible pathname to a specific element.

Answered by cg@miaow.com

1.2.15 What's the difference between %u and %[owner]p ?

%u designates the user who created the object or event, and %[owner]p is the actual owner. This can be confusing when you change ownerships of elements and expect %u to return the owner.

1.3 Queries

1.3.1 How to see what changed between two labels?

Assuming that you always label all visible elements, and assuming that LABEL1 is applied prior to LABEL2, the following will do:

1. In a view selecting LABEL1, run this to obtain those elements which have been unlinked in LABEL2

   % ct find someplace -element 'lbtype_sub(LABEL1) && !lbtype_sub(LABEL2)'\
   
                   -print
   
   

2. In a view selecting LABEL2, run this to obtain those elements which have been added since LABEL1:

   % ct find vobtag> -element 'lbtype_sub(LABEL2) && !lbtype_sub(LABEL1)'\
   
                   -print
   
   

3. In the same view, locate those versions that have changed since LABEL1. Note that this will include elements found in (2).

   % ct find vobtag -version 'lbtype(LABEL2) && !lbtype(LABEL1)'
   
   

1.3.1a How to see what changed between two timestamps?

Use the created_since query construct, like so:

% ct find vobtag -version 'created_since(early) && !created_since(later)'

Note that this will exclude versions created exactly at timestamp later, so it's not an excact equivalent of the label based queries described in 1.3.1.

1.3.2 how to determine the vob of an element?

% ct lsvob pathname

1.3.3 findmerge takes forever on a single element

In order to set up a merge, findmerge needs to find the common ancestor of two versions. In complicated version trees, there can be many common ancestors, and finding the best one requires a non-trivial graph traversal algorithm.

The main problem is that while findmerge is looking for a common ancestor, it is holding a lock on the vob DB, preventing others from writing to the DB. In order to prevent an inordinately long amount of time in the lock, findmerge will interrupt its search, release and reacquire the lock and restart it at ever increasing intervals. There are two environment variables that can be used to tweak this behaviour, which may improve performance for specific elements:

CLEARCASE_FM_TRANS_THRESHOLD(default: 128)

This is the base value for how many versions are examined prior to a restart. This value is doubled, tripled etc as needed after every restart. Increasing this value will avoid a restart in those cases where it was "almost there", but may increase the risk that other developers will experience vob DB timeouts.

CLEARCASE_FM_MAX_LEVEL(default: 65536)

This sets the maximum number of calls that will be made in the quest for the best common ancestor. This value is set very high by default. Setting this to a low value will definitely acceletate findmerge, but may cause it to choose a very old common ancestor, forcing the merge to step through many many old changes.

Check out tech note 747 for more details.

1.3.4 findmerge takes forever over a vob

There are two good techniques to speed up findmerge, often by orders of magnitude:

• Use -fver instead of -ftag. Unless you have a very unusual situation, -fver should be good enough.
• Add -element queries to restrict the number of elements tested. If, for example, you use the common development branch/delivery branch technique, and want to merge the latest from the delivery branch into your development branch, you really only need to consider those elements that have a development branch. So, using the following command instead of a straight findmerge can result in huge performance improvements:

  % ct findmerge someplace\
  
                -element 'brtype(dev_branch)'\
  
                -fver .../del_branch/LATEST -merge
  
  

Using -avobs instead of recursive descent can also improve performance, but is a more risky techniques if directory merges are involved. Since you don't control the order of merges when using -avobs, you could conceivably merge a directory element which isn't visible yet because the parent directory element hasn't been merged yet. Using -avobs -visible will avoid error messages, but may cause you to miss some merges entirely.

1.4 Views & Config Specs

1.4.1 Why do people put /main/0 at the end of a config spec?

This is a good interview question... A typical development config spec looks like this:

element * CHECKEDOUT

element * .../mybranch/LATEST

element * BASELINE -mkbranch mybranch

element * /main/0 -mkbranch mybranch

or like this:

element * CHECKEDOUT

element * .../mybranch/LATEST

element * .../deliverybranch/LATEST -time sometime -mkbranch mybranch

element * /main/0 -mkbranch mybranch

They all contain the /main/0 rule at end because otherwise, you couldn't create new elements. When you create a new element, it will only have a /main/0 version. It wouldn't have a "mybranch" branch, nor a BASELINE label (in the first config spec) and wouldn't have a "deliverybranch" either. Therefore, right after the element was borne, it would disappear from your view since no valid version is selected and the -mkbranch operation couldn't take place. Adding the /main/0 rule ensures that you can always see a newly created element.

The typical follow-up interview question then is: "if everybody uses /main/0, how come I can't see somebody else's new element?". This is a consequence of directory versioning. In fact, two conditions must be satisfied if you are to see a specific element in your view:

• Your config spec must select a valid version
• Your config spec must select a version of the containing directory that has a link to that element.

It is easy to see that the second condition is not satisfied for other users who use their own development branches.

Well, why not use /main/LATEST instead of /main/0?

Using /main/LATEST may hide labeling errors. Suppose, for example, that there are elements that are missing the BASELINE label for some reason, and you are using a config spec like the first one above. If you use /main/0, you will get empty files and empty directories for such elements, which have a good chance of at least causing some visible warning or error at build time. If you use /main/LATEST, you may end up using the wrong version and not notice it.

There is yet another case where /main/0 is required, and is only indirectly related to creating new elements: intentionally empty directories or files.

When one creates an empty directory or file and later merges it onto a new branch, the findmerge algorithm will notice that the base contributor (/main/0) and the target contributor (also /main/0) are identical, and since the source contributor is empty it will skip the copy merge, leaving you with nothing. Therefore, you need to select /main/0 even in a config spec where no new elements are created, such as:

element * .../deliverybranch/LATEST -nocheckout

element * /main/0 -nocheckout

Oh, and how come Rational's documentation uses /main/LATEST all over the place? My guess it that it's a holdover from old documents, where more complex config specs were derived from the default config spec. It is a non-obvious step to replace main/LATEST with main/0, and even to this day, many people think that there is some kind of obligation to merge back into main...

1.4.2 I see checkouts to a view that no longer exists; how do I get rid of them?

First figure out the UUID of the view by running:

% cleartool describe -long vob:vobtag

versioned object base "vobtag"

 created 31-Dec-00.16:23:00 by ClearCase VOB admin account (vobadm.staff)

 VOB family feature level: 2

 VOB storage host:pathname "someplace"

 VOB storage global pathname "someplace"

 database schema version: 53

 VOB ownership:

   owner someone

   group some group

 Additional groups:

   ...

 VOB holds objects from the following views:

   ? [uuid c00c3821.f94411d4.ba94.00:01:80:a9:33:fe]

   ...

You then can remove all the references to the non-existing view by running:

% cleartool rmview -force -avobs -uuid c00c3821.f94411d4.ba94.00:01:80:a9:33:fe

Removing references ...

1.4.3 How do I rename a view?

First end the view server processes by entering:

% cleartool endview -server oldtag

If the view is used on multiple clients, you may have to go from client to client to terminate the view, otherwise you may later get "stale NFS file handle" error messages and possible hangups.

You then remove the view tag using the rmtag command:

% cleartool rmtag -view oldtag

If you also want to rename or relocate the storage directory, unregister the current location, rename and register the new location:

% cleartool unregister -view old-location



% mv old-location new-location



% cleartool register -view new-location

Now you can create a new tag using mktag:

% cleartool mktag -view -tag newtag new-location

You may need to specify more arguments (triple path) depending on the type of the view. You essentially need to replicate most of the arguments you used when creating the view.

1.4.4 How can I keep people from changing their config specs? (Evelyn Leeper )

You can experiment with setting various access permissions in the view stoirage directory, but this isn't really recommended. Instead, you should figure out why developers are changing the config specs and why this would be a problem.

My prefered method for dealing with this is to encourage the use of view maintenance wrapper script that include config spec generators. These scripts should fit in flawlessly with your process and simplify it. Your measure of success will be whether the developers prefer the scripts to hacking their own config specs.

1.4.5 How can I keep people from creating views? (Evelyn Leeper )

You can't and shouldn't, at least for those people who need access to the code. Obviously, you need to keep unauthorized people away, but this can be accomplished by properly setting access permissions to vobs. In other words, you can't prevent people from creating views but you can prevent them from seeing anything with them.

Views really are light weight and ephermal. Creating views shouldn't be a big deal. Your change process should encourage people to check in their work often and essentially treat views as temporary storage areas.

1.4.6 The message says: see view_log on server server-name. Where are the logfiles stored? (Frederick Sena )

They are located on the machine that serves the view. You can determine this machine by running:

% cleartool lsview -long viewtag

% ct lsview -l lt

Tag: viewtag

 Global path: someplace

 Server host: view-server

 Region: this-region

 Active: YES

 View tag uuid:48b5b6f8.752b11d4.a259.00:01:80:a9:33:fe

 View export ID (registry): 18

 ...

1.4.7 How to I cleanup view private files from my view? (Frederick Sena )

1.4.8 How do I recover stranded view private files?

1.4.9 How to I remove a view owned by some else, e.g: someone who left the company? (Frederick Sena )

1.4.10 Why do I get "Checked-out version is not selected by view." when I try to check out a file? (Frederick Sena )

1.4.11 Why do I get "permission denied" when I try to checkout a file in someone else's view? (Frederick Sena )

1.4.12 How to list all of the files in my view that have never been checked-in to the VOB (Bygland, Brian )

1.4.13 Why deal with the "linked storage area"?

The "linked storage area" is the physical storage location of view private files. This storage location can be on external devices, for example filers, whereas the view database storage needs to be on a local disk.

Recent versions of ClearCase have relaxed this condition somehwat, and if you're using filer hardware recommended by Rational, you can put the whole view storage directory on the filer. In other words, linked storage areas are somewhat obsolescent and designed to work around a problem that is disappearing.

1.5 Vobs

1.5.1 what is the recommended vob size?

1.5.2 How (and why) do I split vobs?

1.5.3 Why do I have to lock vobs prior to backing them up?

1.5.4 Why deal with storage pools?

1.5.5 I see a hyperlink described as "? -> ?". How do I get rid of it?

1.5.6 How do I rename a vob?

1.5.7 What are adminvobs? (Sakib Bhola )

1.5.8 What is in lost+found? ()

1.5.9 The VOB is Empty! Where did it go? How to Mount a VOB

1.6 Clearmake, DO's and Winkins

1.6.1 How to list all of the Derived Objects stored within a ClearCase VOB in the current view? Bygland, Brian

1.6.2 How to remove derived objects? Bygland, Brian

1.7 Process, Policies etc

1.7.1 Commonly used triggers?

1.7.2 How can I visualize the branching policy used at a site?

The following script will take as input the output of any set of "lsvtree -short" commands, for example the output produced by:

% cleartool find . -print | xargs cleartool lsvtree -s

It will then produce an indented list of branch/sub-branch relationships and also detect cycles (for example if you have both /main/x/y and /main/y/x).

#!/bin/perl



while (<>) {

 next unless m,\@\@/(main/[^\@]*)$,;

 $branches = $1;

 @branches = split('/', $branches);

 pop(@branches);  # remove version

 $parent = shift; # parent is first entry (main)

 for $branch (@branches) {

   $ancestor_of{$branch}{$parent} = 1;

   $offspring_of{$parent}{$branch} = 1;

   $parent = $branch;

 }

}



make_node('main', 0);



sub make_node {

 my ($parent, $indent) = @_;



 print(' 'x$indent.$parent."\n");

 my $children = 0;

 my @offspring = sort(keys(%{$offspring_of{$parent}}));

 for my $child (@offspring) {

   if (scalar(keys(%{$ancestor_of{$child}})) == 1) {

     # a "real" child is one that has only one ancestor: $parent

     $children = 1;

     make_node($child, $indent+2);

   }

 }

 if (@offspring && !$children) {

   print(' 'x$indent.'  Cycle detected: '.join(' ',@offspring)."\n");

 }

}

1.7.3 Commonly used branching policies

ClearCase Interview 1

What does aldb_server do?


The ClearCase ALBD (ALBD stands for the Atria Location
Broker Daemon) Atria was the name of the company that
originally designed and developed ClearCase) server is a
broker between ClearCase processes and data. It provides
other ClearCase processes with the information needed to
locate and communicate with other ClearCase processes,
regardless of where in the network the processes exist.


Advantages of Rational ClearCase over other SCM tool i.e
Microsoft Visual Source Safe?

The multisite is the best part of clearcase than any other


Different file systems in LIUNX OS?

special files like
pipe,socket

ordinary file
tool


Mention any 5 best SCM practices?

Organize versioned artifacts into versioned components.

Organize versioned components and subsystems into versioned
subsystems.

Create baselines at project milestones.

Record and track requests for change.

Organize and integrate consistent sets of versions using
activities.

Maintain stable and consistent workspaces.





What are version control tools? How are they use full can
any body name few version control tools?

Version control : versioning is the making of copies of data
at some meaningful point in order to return to that point at
a later date, if necessary.

In Software feild so many version control tool are there

SCM tool
VSS tool
cvs tool
pvcs tool

Rational clearcase proides tool support versions all types
file and directories in source repositry .
software feild best version tool is clearcase it support
version control,merging,compare version of software
resource,parallel development...

Version control tools help multiple users to make
simultaneous changes to a collection of documents/files,
without clobbering each others' work or resulting in version
confusion