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Use the SHOW command to get status of the LOCK mechanism and the LOCK database. The format of the SHOWcommand is:

SH[OW] [-qualifier...]

The optional qualifiers are:

-A[LL]
-L[OCK] 
-[NO]C[RIT] 
-O[UTPUT]="file-name"
-P[ID]=pid 
-R[EGION]=region-name 
-W[AIT]

By default, SHOW displays -A[LL].
The SHOW command reports active LOCKs. Information includes the LOCK resource name and the process identification (PID) of the LOCK owner. The results of a SHOW may be immediately "outdated" by M LOCK activity.
If the LOCK is owned by a GT.CM server on behalf of a client GT.M process, then LKE SHOW displays the client NODENAME (limited to the first 15 characters) and clientPID. The client PID (CLNTPID) is a decimal value in UNIX.
GT.CM is an RPC-like way of remotely accessing a GT.M database.


GT.CM is an RPC-like way of remotely accessing a GT.M database.

-ALL

Specifies all current LOCKs.

-ALL displays all current LOCKs in all regions and information about the state of processes owning these LOCKs.
The -ALL qualifier is compatible with all other qualifiers.
When -ALL is combined with -PID or -REGION, the most restrictive qualifier prevails.
SHOW -ALL and -WAIT displays both -ALL and -WAIT information.

-L[OCK]=resource_name

resource_name specifies a single lock.

The resource_name is enclosed in double quotation marks ("" ""). Because M resource names are formatted the same as global nodes with punctuation characters, in this context they are usually enclosed in sets of double quotation marks with string subscripts enclosed in sets of two double quotations.
When used with the CLEAR command, the LOCK qualifier removes the specified lock.
When used with the SHOW command, the LOCK qualifier provides a precise way to examine the specified lock and any descendant LOCKed resources.

-[NO]C[RIT]

Allows the SHOW command to work even if another process is holding a critical section.

By default LKE operates in CRIT mode and ensures a consistent view of LOCKs by using the database critical section(s).
Use NOCRIT with SHOW only when normal operation is unsuccessful, as NOCRIT may cause LKE to report incomplete or inconsistent information.

-O[UTPUT]="file-name"

Directs the reporting of all specified LOCKs to a file.

If you specify an existing file, LKE creates a new version and overwrites that file.
The -OUTPUT qualifier is compatible with all other qualifiers.
By default, the SHOW command send output messages to stdout.

-P[ID]=pid

Specifies the process identification number that holds a LOCK on a resource name.

LKE interprets pid as a decimal number.
PID displays all LOCKs owned by the specified process identification number.
The -PID qualifier is compatible with all other qualifiers; the most restrictive of the qualifiers prevails.
By default, SHOW displays the LOCKs for all PIDs.

-R[EGION]=region-name

Specifies the region that holds the locked resource names.

The REGION qualifier displays LOCKs of that specified region.
The REGION qualifier is compatible with all other qualifiers; the most restrictive of the qualifiers prevails.
By default, SHOW displays the LOCKs for all regions.

-W[AIT]

Displays the LOCK resource name and the process state information of all processes waiting for the LOCK to be granted.

SHOW -WAIT does not display the owner of the LOCK.
SHOW -ALL -WAIT displays both -ALL and -WAIT information.
When a process abandons a "wait" request, that request may continue to appear in LKE SHOW -WAIT displays. This appearance is harmless, and is automatically eliminated if the GT.M lock management requires the space which it occupies.

Use the following procedure to display all LOCKs active in the database(s) defined by the current global directory.

LKE> SHOW -ALL -WAIT

This produces an output like the following:

No locks were found in DEFAULT 
AREG 
^a Owned by PID=2080 which is an existing process 
BREG 
^b(2) Owned by PID= 2089 anonexistent process 
Request PID= 20400630 which is HIB 
No locks were found in CREG

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