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Hello.
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Hi,
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5. Programming
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I am looking for C program source code. Could you please help me in finding the source code required mentioned below.
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10. UNIX for Advanced & Expert Users
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ipcs(1) General Commands Manual ipcs(1)
NAME
ipcs - report status of interprocess communication facilities
SYNOPSIS
core] namelist]
DESCRIPTION
displays certain information about active interprocess communication facilities. With no options, displays information in short format for
the message queues, shared memory segments, and semaphores that are currently active in the system.
Options
The following options restrict the display to the corresponding facilities.
(none) This is equivalent to
Display information about active shared memory segments.
Display information about active message queues.
Display information about active semaphores.
The following options add columns of data to the display. See "Column Description" below.
(none) Display default columns: for all facilities:
Display all columns, as appropriate.
This is equivalent to
Display largest-allowable-size information:
for message queues: for shared memory segments: for semaphores:
Display creator's login name and group name:
for all facilities:
Display information on outstanding usage:
for message queues: for shared memory segments:
Display process number information:
for message queues: for shared memory segments:
Display time information:
for all facilities: for message queues: for shared memory segments: for semaphores:
The following options redefine the sources of information.
Use core in place of core can be a core file or a directory created by or
Use file namelist or the namelist within core in place of It opens a crash dump for reading. Please refer to cr_open(3) for
more details.
Column Descriptions
The column headings and the meaning of the columns in an listing are given below. The columns are printed from left to right in the order
shown below.
Facility type:
Shared memory segment
Message queue
Semaphore
The identifier for the facility entry.
The key used as an argument to
or to create the facility entry. (Note: The key of a shared memory segment is changed to when the segment has been removed until
all processes attached to the segment detach it.)
The facility access modes and flags:
The mode consists of 11 characters that are interpreted as follows:
The first two characters can be:
A process is waiting on a
A process is waiting on a
The associated shared memory segment has been removed.
It will disappear when the last process attached to the segment detaches it.
The associated shared memory segment is to be cleared when the
first attach is executed.
The corresponding special flag is not set.
The next 9 characters are interpreted as three sets of three characters each. The first set refers to the owner's permissions, the
next to permissions of others in the group of the facility entry, and the last to all others.
Within each set, the first character indicates permission to read, the second character indicates permission to write or alter the
facility entry, and the last character is currently unused.
Read permission is granted.
Write permission is granted.
Alter permission is granted.
The indicated permission is not granted.
The login name of the owner of the facility entry.
The group name of the group of the owner of the facility entry.
The login name of the creator of the facility entry.
The group name of the group of the creator of the facility entry.
The number of bytes in messages
currently outstanding on the associated message queue.
The number of messages currently outstanding
on the associated message queue.
The maximum number of bytes allowed
in messages outstanding on the associated message queue.
The process ID of the last process to send a message
to the associated message queue.
The process ID of the last process to receive a message
from the associated message queue.
The time the last
message was sent to the associated message queue.
The time the last
message was received from the associated message queue.
The time when the associated facility entry was created or changed.
The number of processes attached to the associated shared memory segment.
The size of the associated shared memory segment.
The process ID of the creating process of the shared memory segment.
The process ID of the last process
to attach or detach the shared memory segment.
The time the last
attach was completed to the associated shared memory segment.
The time the last
detach was completed on the associated shared memory segment.
The number of semaphores in the set associated with the semaphore entry.
The time the last
semaphore operation was completed on the set associated with the semaphore entry.
WARNINGS
produces only an approximate indication of actual system status because system processes are continually changing while is acquiring the
requested information.
Do not rely on the exact field widths and spacing of the output, as these will vary depending on the system, the release of HP-UX, and the
data to be displayed.
FILES
Kernel virtual memory
Group names
User names
System namelist
SEE ALSO
msgop(2), semop(2), shmop(2).
STANDARDS CONFORMANCE
ipcs(1)