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Annotation of cci/usr/src/man/man2/msgget.2i, revision 1.1.1.1

1.1       root        1: .TH MSGGET 2
                      2: .SH NAME
                      3: msgget \- get message queue
                      4: .SH SYNOPSIS
                      5: .B #include <sys/types.h>
                      6: .br
                      7: .B #include <sys/ipc.h>
                      8: .br
                      9: .B #include <sys/msg.h>
                     10: .PP
                     11: .nf
                     12: .B "int msgget (key, msgflg)"
                     13: .B key_t key;
                     14: .B int msgflg;
                     15: .fi
                     16: .SH DESCRIPTION
                     17: .I Msgget
                     18: returns the message queue identifier associated with
                     19: .IR key .
                     20: .PP
                     21: A message queue identifier and associated message queue and data structure
                     22: (see
                     23: .IR intro (2))
                     24: are created for
                     25: .I key
                     26: if one of the following are true:
                     27: .IP 10
                     28: .I Key
                     29: is equal to
                     30: .SM
                     31: .BR IPC_PRIVATE .
                     32: .IP
                     33: .I Key
                     34: does not already have a message queue identifier associated with it, and
                     35: .RI ( msgflg " & "
                     36: .SM
                     37: .BR IPC_CREAT\*S )
                     38: is ``true''.
                     39: .PP
                     40: Upon creation, the data structure associated with the new message queue
                     41: identifier is initialized as follows:
                     42: .IP
                     43: .BR Msg_perm.cuid ", " msg_perm.uid ,
                     44: .BR msg_perm.cgid ", and " msg_perm.gid
                     45: are set equal to the effective user
                     46: .SM ID
                     47: and effective group
                     48: .SM ID\*S,
                     49: respectively, of the calling process.
                     50: .IP
                     51: The low-order 9 bits of
                     52: .B msg_perm.mode
                     53: are set equal to the low-order 9 bits of
                     54: .IR msgflg .
                     55: .IP
                     56: .BR Msg_qnum ", " msg_lspid ", " msg_lrpid ,
                     57: .BR msg_stime ", and " msg_rtime "
                     58: are set equal to 0.
                     59: .IP
                     60: .B Msg_ctime
                     61: is set equal to the current time.
                     62: .IP
                     63: .B Msg_qbytes
                     64: is set equal to the system limit.
                     65: .PP
                     66: .I Msgget
                     67: will fail if one or more of the following are true:
                     68: .TP 15
                     69: \s-1\%[EACCES]\s+1
                     70: A message queue identifier exists for
                     71: .IR key ,
                     72: but operation permission (see
                     73: .IR intro (2))
                     74: as specified by the low-order 9 bits of
                     75: .I msgflg
                     76: would not be granted. 
                     77: .TP
                     78: \s-1\%[ENOENT]\s+1
                     79: A message queue identifier does not exist for
                     80: .I key
                     81: and
                     82: .RI ( msgflg " &"
                     83: .SM
                     84: .BR IPC_CREAT\*S )
                     85: is ``false''.
                     86: .TP
                     87: \s-1\%[ENOSPC]\s+1
                     88: A message queue identifier is to be created but
                     89: the system-imposed limit on the maximum number of
                     90: allowed message queue identifiers system wide
                     91: would be exceeded.
                     92: .TP
                     93: \s-1\%[EEXIST]\s+1
                     94: A message queue identifier exists for
                     95: .I key
                     96: but
                     97: .RI "((" msgflg " & "
                     98: .SM
                     99: .RB IPC_CREAT\*S ") & ("
                    100: .IR msgflg " & "
                    101: .SM
                    102: .BR IPC_EXCL\*S "))"
                    103: is ``true''.
                    104: .SH "RETURN VALUE"
                    105: Upon successful completion,
                    106: a non-negative integer,
                    107: namely a message queue identifier, is returned.
                    108: Otherwise, a value of \-1 is returned and
                    109: .I errno\^
                    110: is set to indicate the error.
                    111: .SH SEE ALSO
                    112: intro(2), msgctl(2), msgop(2).
                    113: .\"    @(#)msgget.2    6.2 of 9/6/83

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