msg(5)                                                               msg(5)

NAME
     msg - message queue structures

SYNOPSIS
     #include <sys/msg.h>

DESCRIPTION
     The <sys/msg.h> header defines the following constant and members of
     the structure msqidds.

     The following data types are defined through typedef:

     msgqnumt           Used for the number of messages in the message
                         queue.

     msglent            Used for the number of bytes allowed in a message
                         queue.

     These types are unsigned integer types that are able to store values
     at least as large as a type unsigned short.

     Message operation flag:

     MSGNOERROR         No error if big message.

     The structure msqidds contains the following members:

     struct ipcperm  msgperm     operation permission structure

     msgqnumt        msgqnum     number of messages currently on queue

     msglent         msgqbytes   maximum number of bytes allowed on queue

     pidt            msglspid    process ID of last msgsnd()

     pidt            msglrpid    process ID of last msgrcv()

     timet           msgstime    time of last msgsnd()

     timet           msgrtime    time of last msgrcv()

     timet           msgctime    time of last change

     The pidt, timet, keyt and sizet types are defined as described in
     <sys/types.h>.










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msg(5)                                                               msg(5)

     The following are declared as functions and may also be defined as
     macros:

     int   msgctl(int msqid, int cmd, struct msqidds *buf);
     int   msgget(keyt key, int msgflg);
     int   msgrcv(int msqid, void *msgp, sizet msgsz, long int msgtyp,
                  int msgflg);
     int   msgsnd(int msqid, const void *msgp, sizet msgsz, int msgflg);

     In addition, all of the symbols from <sys/ipc.h> will be defined when
     this header is included.

SEE ALSO
     msgctl(2), msgget(2), msgrcv(2), msgsnd(2), types(5).








































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