msgctl man page on Tru64

Man page or keyword search:  
man Server   12896 pages
apropos Keyword Search (all sections)
Output format
Tru64 logo
[printable version]

msgctl(2)							     msgctl(2)

NAME
       msgctl - Perform message control operations

SYNOPSIS
       #include <sys/msg.h>

       int msgctl(
	       int msqid,
	       int cmd,
	       struct msqid_ds *buf );

       Application  developers	might  want to specify #include statements for
       <sys/types.h> and <sys/ipc.h> before the one for	 <sys/msg.h>  if  pro‐
       grams  are  being  developed  for  multiple  platforms.	The additional
       #include statements are not required on Tru64 UNIX systems or by ISO or
       X/Open  standards,  but	may be required on other vendors' systems that
       conform to these standards.

STANDARDS
       Interfaces documented on this reference page conform to industry	 stan‐
       dards as follows:

       msgctl():  XSH4.0, XSH4.2, XSH5.0

       Refer  to  the  standards(5)  reference page for more information about
       industry standards and associated tags.

PARAMETERS
       Specifies the message queue ID.	Specifies the  type  of	 command.  The
       possible	 commands  and	the  operations	 they  perform are as follows:
       Queries the message queue ID by copying the contents of its  associated
       data structure into the buf structure.  The process must have mandatory
       read access to the message queue with respect  to  all  access  control
       policies.  Sets the message queue ID by copying values found in the buf
       structure into corresponding fields in the msqid_ds  structure  associ‐
       ated  with  the	message	 queue	ID.  This operation is restricted. The
       effective user ID of the calling process must be equal to that of supe‐
       ruser  or  equal	 to  the value of msg_perm.uid or msg_perm.cuid in the
       associated msqid_ds structure.  Only superuser can raise the  value  of
       msg_qbytes.   Removes  the message queue ID and deallocates its associ‐
       ated msqid_ds structure. This operation is  restricted.	The  effective
       user  ID	 of  the calling process must be equal to that of superuser or
       equal to the value of msg_perm.uid or msg_perm.cuid in  the  associated
       msqid_ds structure.  Points to an msqid_ds structure. This structure is
       used only with the IPC_STAT and IPC_SET commands.  With	IPC_STAT,  the
       results	of  the query are copied to this structure.  With IPC_SET, the
       values in this structure are used to set the  corresponding  fields  in
       the  msqid_ds structure associated with the message queue ID. In either
       case, the calling process must have allocated the structure before mak‐
       ing the call.

DESCRIPTION
       The  msgctl() function allows a process to query or set the contents of
       the msqid_ds structure associated with the specified message queue  ID.
       It also allows a process to remove the message queue ID and its associ‐
       ated msqid_ds structure.	 The cmd value determines which	 operation  is
       performed.

       The  IPC_SET  command uses the user-supplied contents of the buf struc‐
       ture to set the following members of the msqid_ds structure  associated
       with  the message queue ID: The owner's user ID.	 The owner's group ID.
       The access modes for the queue. Only the low-order nine bits  are  set.
       The  maximum  number  of bytes on the queue.  The time of the last suc‐
       cessful IPC_SET operation.

RETURN VALUES
       Upon successful completion, msgctl() returns a value of 0 (zero).  Oth‐
       erwise,	a  value  of  -1  is returned and errno is set to indicate the
       error.

ERRORS
       The msgctl() function sets errno to the specified values for  the  fol‐
       lowing  conditions:  The	 cmd  parameter	 is  IPC_STAT, but the calling
       process does not have read permission.  [Tru64 UNIX]  The cmd parameter
       is  IPC_STAT  or	 IPC_SET,  and	an error occurred in accessing the buf
       structure.  The msqid parameter is not a valid message queue ID, or the
       cmd  parameter  is not a valid command.	One of the following occurred:
       The cmd parameter is equal to either IPC_RMID or IPC_SET, and the call‐
       ing  process does not have appropriate privilege.  The cmd parameter is
       equal to IPC_SET, and an attempt is being made to increase the value of
       the  msg_qbytes	parameter  when	 the calling process does not have the
       superuser privilege.

SEE ALSO
       Functions: msgget(2), msgrcv(2), msgsnd(2)

       Data Structures: msqid_ds(4)

       Standards: standards(5)

								     msgctl(2)
[top]
                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server Tru64

List of man pages available for Tru64

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net