Return to mesg_port.3 CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / libpdel / util

Annotation of embedaddon/libpdel/util/mesg_port.3, revision 1.1

1.1     ! misho       1: .\" Copyright (c) 2001-2002 Packet Design, LLC.
        !             2: .\" All rights reserved.
        !             3: .\" 
        !             4: .\" Subject to the following obligations and disclaimer of warranty,
        !             5: .\" use and redistribution of this software, in source or object code
        !             6: .\" forms, with or without modifications are expressly permitted by
        !             7: .\" Packet Design; provided, however, that:
        !             8: .\" 
        !             9: .\"    (i)  Any and all reproductions of the source or object code
        !            10: .\"         must include the copyright notice above and the following
        !            11: .\"         disclaimer of warranties; and
        !            12: .\"    (ii) No rights are granted, in any manner or form, to use
        !            13: .\"         Packet Design trademarks, including the mark "PACKET DESIGN"
        !            14: .\"         on advertising, endorsements, or otherwise except as such
        !            15: .\"         appears in the above copyright notice or in the software.
        !            16: .\" 
        !            17: .\" THIS SOFTWARE IS BEING PROVIDED BY PACKET DESIGN "AS IS", AND
        !            18: .\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, PACKET DESIGN MAKES NO
        !            19: .\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING
        !            20: .\" THIS SOFTWARE, INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED
        !            21: .\" WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
        !            22: .\" OR NON-INFRINGEMENT.  PACKET DESIGN DOES NOT WARRANT, GUARANTEE,
        !            23: .\" OR MAKE ANY REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS
        !            24: .\" OF THE USE OF THIS SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY,
        !            25: .\" RELIABILITY OR OTHERWISE.  IN NO EVENT SHALL PACKET DESIGN BE
        !            26: .\" LIABLE FOR ANY DAMAGES RESULTING FROM OR ARISING OUT OF ANY USE
        !            27: .\" OF THIS SOFTWARE, INCLUDING WITHOUT LIMITATION, ANY DIRECT,
        !            28: .\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, PUNITIVE, OR CONSEQUENTIAL
        !            29: .\" DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, LOSS OF
        !            30: .\" USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY THEORY OF
        !            31: .\" LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
        !            32: .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
        !            33: .\" THE USE OF THIS SOFTWARE, EVEN IF PACKET DESIGN IS ADVISED OF
        !            34: .\" THE POSSIBILITY OF SUCH DAMAGE.
        !            35: .\"
        !            36: .\" Author: Archie Cobbs <archie@freebsd.org>
        !            37: .\"
        !            38: .\" $Id: mesg_port.3,v 1.7 2004/06/02 17:24:38 archie Exp $
        !            39: .\"
        !            40: .Dd April 22, 2002
        !            41: .Dt MESG_PORT 3
        !            42: .Os
        !            43: .Sh NAME
        !            44: .Nm mesg_port
        !            45: .Nd generic message ports
        !            46: .Sh LIBRARY
        !            47: PDEL Library (libpdel, \-lpdel)
        !            48: .Sh SYNOPSIS
        !            49: .In pthread.h
        !            50: .In pdel/util/mesg_port.h
        !            51: .Ft "struct mesg_port *"
        !            52: .Fn mesg_port_create "const char *mtype"
        !            53: .Ft void
        !            54: .Fn mesg_port_destroy "struct mesg_port **portp"
        !            55: .Ft int
        !            56: .Fn mesg_port_put "struct mesg_port *port" "void *data"
        !            57: .Ft "void *"
        !            58: .Fn mesg_port_get "struct mesg_port *port" "int timeout"
        !            59: .Ft u_int
        !            60: .Fn mesg_port_qlen "struct mesg_port *port"
        !            61: .Sh DESCRIPTION
        !            62: These functions implement a message port for inter-thread communication.
        !            63: .Pp
        !            64: .Fn mesg_port_create
        !            65: creates a new messge port, using
        !            66: .Xr typed_mem 3
        !            67: type
        !            68: .Fa mtype
        !            69: for internal memory allocation.
        !            70: .Pp
        !            71: .Fn mesg_port_destroy
        !            72: destroys the message port pointed to by
        !            73: .Fa "*portp" .
        !            74: There must be no messages in the message port, otherwise
        !            75: .Fn mesg_port_destroy
        !            76: aborts with an assertion failure.
        !            77: Upon return,
        !            78: .Fa "*portp"
        !            79: will be set to
        !            80: .Dv NULL .
        !            81: If
        !            82: .Fa "*portp"
        !            83: is already
        !            84: .Dv NULL
        !            85: when
        !            86: .Fn mesg_port_destroy
        !            87: is invoked, nothing happens.
        !            88: .Pp
        !            89: .Fn mesg_port_put
        !            90: writes the message represented by
        !            91: .Fa data
        !            92: to the message port pointed to by
        !            93: .Fa port .
        !            94: The
        !            95: .Fa data
        !            96: may not be
        !            97: .Dv NULL .
        !            98: .Pp
        !            99: .Fn mesg_port_get
        !           100: retrieves the next available message written to the message port pointed to by
        !           101: .Fa port .
        !           102: Messages are read in the same order as they are written.
        !           103: If there are no messages,
        !           104: .Fn mesg_port_get
        !           105: waits for up to
        !           106: .Fa timeout
        !           107: milliseconds, or indefinitely if
        !           108: .Fa timeout
        !           109: is negative.
        !           110: The thread calling
        !           111: .Fn mesg_port_get
        !           112: may be canceled without ill effect.
        !           113: .Pp
        !           114: .Fn mesg_port_qlen
        !           115: returns the current number of messages queued on the message port pointed to by
        !           116: .Fa port .
        !           117: .Pp
        !           118: .Fn mesg_port_put ,
        !           119: .Fn mesg_port_get ,
        !           120: and
        !           121: .Fn mesg_port_qlen
        !           122: may be called safely at the same time from different threads.
        !           123: .Sh RETURN VALUES
        !           124: .Fn mesg_port_create ,
        !           125: .Fn mesg_port_put ,
        !           126: and
        !           127: .Fn mesg_port_get
        !           128: return
        !           129: .Dv NULL
        !           130: or -1 to indicate an error,
        !           131: with
        !           132: .Va errno
        !           133: set appropriately.
        !           134: .Sh SEE ALSO
        !           135: .Xr libpdel 3 ,
        !           136: .Xr pevent 3 ,
        !           137: .Xr pthread 3 ,
        !           138: .Xr typed_mem 3
        !           139: .Sh HISTORY
        !           140: The PDEL library was developed at Packet Design, LLC.
        !           141: .Dv "http://www.packetdesign.com/"
        !           142: .Sh AUTHORS
        !           143: .An Archie Cobbs Aq archie@freebsd.org