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added queue(3), psignal(3) man pages
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usr.man/man3/psignal.3
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91
usr.man/man3/psignal.3
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@ -0,0 +1,91 @@
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.\" Copyright (c) 1983, 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
|
||||
.\"
|
||||
.\" Redistribution and use in source and binary forms, with or without
|
||||
.\" modification, are permitted provided that the following conditions
|
||||
.\" are met:
|
||||
.\" 1. Redistributions of source code must retain the above copyright
|
||||
.\" notice, this list of conditions and the following disclaimer.
|
||||
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||
.\" notice, this list of conditions and the following disclaimer in the
|
||||
.\" documentation and/or other materials provided with the distribution.
|
||||
.\" 3. All advertising materials mentioning features or use of this software
|
||||
.\" must display the following acknowledgement:
|
||||
.\" This product includes software developed by the University of
|
||||
.\" California, Berkeley and its contributors.
|
||||
.\" 4. Neither the name of the University nor the names of its contributors
|
||||
.\" may be used to endorse or promote products derived from this software
|
||||
.\" without specific prior written permission.
|
||||
.\"
|
||||
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
||||
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
||||
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)psignal.3 8.1 (Berkeley) 6/4/93
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.\"
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.TH PSIGNAL 3 "27 July 1997" GNO "Library Routines"
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.SH NAME
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.BR psignal ,
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.BR sys_siglist ,
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.BR sys_signame
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\- system signal messages
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.SH SYNOPSIS
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#include <sys/signal.h>
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.sp 1
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void
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\fBpsignal\fR (unsigned \fIsig\fR, const char *\fIs\fR);
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.sp 1
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extern const char * const \fBsys_siglist\fR[];
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.br
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extern const char * const \fBsys_signame\fR[];
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.SH DESCRIPTION
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The
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.BR psignal
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function locates the descriptive message
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string for the given signal number
|
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.I sig
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and writes it to the standard error.
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.LP
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If the argument
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||||
.I s
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is non-NULL,
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it is written to the standard error file descriptor
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prior to the message string,
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immediately followed by a colon and a space.
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If the signal number is not recognized (see
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.BR sigaction (2)),
|
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the string
|
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.I "Unknown signal"
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is produced.
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.LP
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The message strings can be accessed directly
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through the external array
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.IR sys_siglist ,
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indexed by recognized signal numbers.
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The external array
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.IR sys_signame
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is used similarly and
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contains short, lower-case abbreviations for signals
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which are useful for recognizing signal names
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in user input.
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The defined macro
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.BR NSIG
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contains a count of the strings in
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.IR sys_siglist
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and
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.IR sys_signame .
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.SH SEE ALSO
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.BR sigaction (2),
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.BR perror (3)
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.SH HISTORY
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The
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.BR psignal
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function appeared in 4.2BSD.
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876
usr.man/man3/queue.3
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876
usr.man/man3/queue.3
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@ -0,0 +1,876 @@
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.\" Copyright (c) 1993
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.\" The Regents of the University of California. All rights reserved.
|
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.\"
|
||||
.\" Redistribution and use in source and binary forms, with or without
|
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.\" modification, are permitted provided that the following conditions
|
||||
.\" are met:
|
||||
.\" 1. Redistributions of source code must retain the above copyright
|
||||
.\" notice, this list of conditions and the following disclaimer.
|
||||
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||
.\" notice, this list of conditions and the following disclaimer in the
|
||||
.\" documentation and/or other materials provided with the distribution.
|
||||
.\" 3. All advertising materials mentioning features or use of this software
|
||||
.\" must display the following acknowledgement:
|
||||
.\" This product includes software developed by the University of
|
||||
.\" California, Berkeley and its contributors.
|
||||
.\" 4. Neither the name of the University nor the names of its contributors
|
||||
.\" may be used to endorse or promote products derived from this software
|
||||
.\" without specific prior written permission.
|
||||
.\"
|
||||
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
||||
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
||||
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)queue.3 8.2 (Berkeley) 1/24/94
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.\"
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.TH QUEUE 3 "11 May 1997" GNO "Library Routines"
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.SH NAME
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.BR SLIST_ENTRY ,
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.BR SLIST_HEAD ,
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.BR SLIST_INIT ,
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.BR SLIST_INSERT_AFTER ,
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.BR SLIST_INSERT_HEAD ,
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.BR SLIST_REMOVE_HEAD ,
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.BR SLIST_REMOVE ,
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.BR STAILQ_ENTRY ,
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.BR STAILQ_HEAD ,
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.BR STAILQ_INIT ,
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.BR STAILQ_INSERT_AFTER ,
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.BR STAILQ_INSERT_HEAD ,
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.BR STAILQ_INSERT_TAIL ,
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.BR STAILQ_REMOVE_HEAD ,
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.BR STAILQ_REMOVE ,
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.BR LIST_ENTRY ,
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.BR LIST_HEAD ,
|
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.BR LIST_INIT ,
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.BR LIST_INSERT_AFTER ,
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.BR LIST_INSERT_BEFORE ,
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.BR LIST_INSERT_HEAD ,
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.BR LIST_REMOVE ,
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.BR TAILQ_ENTRY ,
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.BR TAILQ_HEAD ,
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.BR TAILQ_INIT ,
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.BR TAILQ_INSERT_AFTER ,
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.BR TAILQ_INSERT_BEFORE ,
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.BR TAILQ_INSERT_HEAD ,
|
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.BR TAILQ_INSERT_TAIL ,
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.BR TAILQ_REMOVE ,
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.BR CIRCLEQ_ENTRY ,
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.BR CIRCLEQ_HEAD ,
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.BR CIRCLEQ_INIT ,
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.BR CIRCLEQ_INSERT_AFTER ,
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.BR CIRCLEQ_INSERT_BEFORE ,
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.BR CIRCLEQ_INSERT_HEAD ,
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.BR CIRCLEQ_INSERT_TAIL ,
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.BR CIRCLEQ_REMOVE
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\- implementations of singly-linked lists, singly-linked tail queues,
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lists, tail queues, and circular queues
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.SH SYNOPSIS
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#include <sys/queue.h>
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.sp 1
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SLIST_ENTRY (TYPE);
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.br
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SLIST_HEAD (HEADNAME, TYPE);
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.br
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SLIST_INIT (SLIST_HEAD *\fIhead\fR);
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.br
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SLIST_INSERT_AFTER (TYPE *\fIlistelm\fR, TYPE *\fIelm\fR, SLIST_ENTRY NAME);
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.br
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SLIST_INSERT_HEAD (SLIST_HEAD *\fIhead\fR, TYPE *\fIelm\fR, SLIST_ENTRY NAME);
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.br
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SLIST_REMOVE_HEAD (SLIST_HEAD *\fIhead\fR, SLIST_ENTRY NAME);
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.br
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SLIST_REMOVE (SLIST_HEAD *\fIhead\fR, TYPE *\fIelm\fR, TYPE, SLIST_ENTRY NAME);
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.sp 1
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STAILQ_ENTRY (TYPE);
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.br
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STAILQ_HEAD (HEADNAME, TYPE);
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.br
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STAILQ_INIT (STAILQ_HEAD *head);
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.br
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STAILQ_INSERT_AFTER (STAILQ_HEAD *\fIhead\fR, TYPE *listelm, TYPE *\fIelm\fR, STAILQ_ENTRY NAME);
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.br
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STAILQ_INSERT_HEAD (STAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, STAILQ_ENTRY NAME);
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.br
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STAILQ_INSERT_TAIL (STAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, STAILQ_ENTRY NAME);
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.br
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STAILQ_REMOVE_HEAD (STAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, STAILQ_ENTRY NAME);
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.br
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STAILQ_REMOVE (STAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, TYPE, STAILQ_ENTRY NAME);
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.sp 1
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LIST_ENTRY (TYPE);
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.br
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LIST_HEAD (HEADNAME, TYPE);
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.br
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LIST_INIT (LIST_HEAD *head);
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.br
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LIST_INSERT_AFTER (TYPE *listelm, TYPE *\fIelm\fR, LIST_ENTRY NAME);
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.br
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LIST_INSERT_BEFORE (TYPE *listelm, TYPE *\fIelm\fR, LIST_ENTRY NAME);
|
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.br
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LIST_INSERT_HEAD (LIST_HEAD *\fIhead\fR, TYPE *\fIelm\fR, LIST_ENTRY NAME);
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.br
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LIST_REMOVE (TYPE *\fIelm\fR, LIST_ENTRY NAME);
|
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.sp 1
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TAILQ_ENTRY (TYPE);
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.br
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TAILQ_HEAD (HEADNAME, TYPE);
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.br
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TAILQ_INIT (TAILQ_HEAD *head);
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.br
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TAILQ_INSERT_AFTER (TAILQ_HEAD *\fIhead\fR, TYPE *listelm, TYPE *\fIelm\fR, TAILQ_ENTRY NAME);
|
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.br
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TAILQ_INSERT_BEFORE (TYPE *listelm, TYPE *\fIelm\fR, TAILQ_ENTRY NAME);
|
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.br
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TAILQ_INSERT_HEAD (TAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, TAILQ_ENTRY NAME);
|
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.br
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TAILQ_INSERT_TAIL (TAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, TAILQ_ENTRY NAME);
|
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.br
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TAILQ_REMOVE (TAILQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, TAILQ_ENTRY NAME);
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.sp 1
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CIRCLEQ_ENTRY (TYPE);
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||||
.br
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CIRCLEQ_HEAD (HEADNAME, TYPE);
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.br
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CIRCLEQ_INIT (CIRCLEQ_HEAD *head);
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.br
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CIRCLEQ_INSERT_AFTER (CIRCLEQ_HEAD *\fIhead\fR, TYPE *listelm, TYPE *\fIelm\fR, CIRCLEQ_ENTRY NAME);
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.br
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CIRCLEQ_INSERT_BEFORE (CIRCLEQ_HEAD *\fIhead\fR, TYPE *listelm, TYPE *\fIelm\fR, CIRCLEQ_ENTRY NAME);
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||||
.br
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||||
CIRCLEQ_INSERT_HEAD (CIRCLEQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, CIRCLEQ_ENTRY NAME);
|
||||
.br
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||||
CIRCLEQ_INSERT_TAIL (CIRCLEQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, CIRCLEQ_ENTRY NAME);
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.br
|
||||
CIRCLEQ_REMOVE (CIRCLEQ_HEAD *\fIhead\fR, TYPE *\fIelm\fR, CIRCLEQ_ENTRY NAME);
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.SH DESCRIPTION
|
||||
These macros define and operate on five types of data structures:
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singly-linked lists, singly-linked tail queues, lists, tail queues,
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and circular queues.
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All five structures support the following functionality:
|
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.RS
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||||
.sp 1
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Insertion of a new entry at the head of the list.
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.br
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||||
Insertion of a new entry after any element in the list.
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.br
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O(1) removal of an entry from the head of the list.
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.br
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O(n) removal of any entry in the list.
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.br
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Forward traversal through the list.
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.RE
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.LP
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Singly-linked lists are the simplest of the five data structures
|
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and support only the above functionality.
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Singly-linked lists are ideal for applications with large datasets
|
||||
and few or no removals,
|
||||
or for implementing a LIFO queue.
|
||||
.LP
|
||||
Singly-linked tail queues add the following functionality:
|
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.RS
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||||
.sp 1
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Entries can be added at the end of a list.
|
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.sp 1
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.RE
|
||||
However:
|
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.RS
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All list insertions must specify the head of the list.
|
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.br
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Each head entry requires two pointers rather than one.
|
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.br
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Code size is about 15% greater and operations run about 20% slower
|
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than singly-linked lists.
|
||||
.RE
|
||||
.LP
|
||||
Singly-linked tailqs are ideal for applications with large datasets and
|
||||
few or no removals,
|
||||
or for implementing a FIFO queue.
|
||||
.LP
|
||||
All doubly linked types of data structures (lists, tail queues, and circle
|
||||
queues) additionally allow:
|
||||
.RS
|
||||
.sp 1
|
||||
Insertion of a new entry before any element in the list.
|
||||
.br
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O(1) removal of any entry in the list.
|
||||
.RE
|
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However:
|
||||
.RS
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Each elements requires two pointers rather than one.
|
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.br
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Code size and execution time of operations (except for removal) is about
|
||||
twice that of the singly-linked data-structures.
|
||||
.RE
|
||||
.LP
|
||||
Linked lists are the simplest of the doubly linked data structures and support
|
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only the above functionality over singly-linked lists.
|
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.LP
|
||||
Tail queues add the following functionality:
|
||||
.RS
|
||||
.sp 1
|
||||
Entries can be added at the end of a list.
|
||||
.RE
|
||||
However:
|
||||
.RS
|
||||
All list insertions and removals must specify the head of the list.
|
||||
.br
|
||||
Each head entry requires two pointers rather than one.
|
||||
.br
|
||||
Code size is about 15% greater and operations run about 20% slower
|
||||
than singly-linked lists.
|
||||
.RE
|
||||
.LP
|
||||
Circular queues add the following functionality:
|
||||
.RS
|
||||
.sp 1
|
||||
Entries can be added at the end of a list.
|
||||
.br
|
||||
They may be traversed backwards, from tail to head.
|
||||
.RE
|
||||
However:
|
||||
.RS
|
||||
All list insertions and removals must specify the head of the list.
|
||||
.br
|
||||
Each head entry requires two pointers rather than one.
|
||||
.br
|
||||
The termination condition for traversal is more complex.
|
||||
.br
|
||||
Code size is about 40% greater and operations run about 45% slower
|
||||
than lists.
|
||||
.RE
|
||||
.LP
|
||||
In the macro definitions,
|
||||
.I TYPE
|
||||
is the name of a user defined structure,
|
||||
that must contain a field of type
|
||||
.BR SLIST_ENTRY ,
|
||||
.BR STAILQ_ENTRY ,
|
||||
.BR LIST_ENTRY ,
|
||||
.BR TAILQ_ENTRY ,
|
||||
or
|
||||
.BR CIRCLEQ_ENTRY ,
|
||||
named
|
||||
.IR NAME
|
||||
The argument
|
||||
.I HEADNAME
|
||||
is the name of a user defined structure that must be declared
|
||||
using the macros
|
||||
.BR SLIST_HEAD ,
|
||||
.BR STAILQ_HEAD ,
|
||||
.BR LIST_HEAD ,
|
||||
.BR TAILQ_HEAD ,
|
||||
or
|
||||
.BR CIRCLEQ_HEAD .
|
||||
See the examples below for further explanation of how these
|
||||
macros are used.
|
||||
.SH SINGLY-LINKED LISTS
|
||||
A singly-linked list is headed by a structure defined by the
|
||||
.BR SLIST_HEAD
|
||||
macro.
|
||||
This structure contains a single pointer to the first element
|
||||
on the list.
|
||||
The elements are singly linked for minimum space and pointer manipulation
|
||||
overhead at the expense of O(n) removal for arbitrary elements.
|
||||
New elements can be added to the list after an existing element or
|
||||
at the head of the list.
|
||||
An
|
||||
.I SLIST_HEAD
|
||||
structure is declared as follows:
|
||||
.RS
|
||||
.sp
|
||||
SLIST_HEAD(HEADNAME, TYPE) head;
|
||||
.sp
|
||||
.RE
|
||||
where
|
||||
.I HEADNAME
|
||||
is the name of the structure to be defined, and
|
||||
.I TYPE
|
||||
is the type of the elements to be linked into the list.
|
||||
A pointer to the head of the list can later be declared as:
|
||||
.RS
|
||||
.sp
|
||||
struct HEADNAME *headp;
|
||||
.sp
|
||||
.RE
|
||||
(The names
|
||||
.IR head
|
||||
and
|
||||
.IR headp
|
||||
are user selectable.)
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_ENTRY
|
||||
declares a structure that connects the elements in
|
||||
the list.
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_INIT
|
||||
initializes the list referenced by
|
||||
.IR head .
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_INSERT_HEAD
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the head of the list.
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_INSERT_AFTER
|
||||
inserts the new element
|
||||
.I elm
|
||||
after the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_REMOVE_HEAD
|
||||
removes the element
|
||||
.I elm
|
||||
from the head of the list.
|
||||
For optimum efficiency,
|
||||
elements being removed from the head of the list should explicitly use
|
||||
this macro instead of the generic
|
||||
.I SLIST_REMOVE
|
||||
macro.
|
||||
.LP
|
||||
The macro
|
||||
.BR SLIST_REMOVE
|
||||
removes the element
|
||||
.I elm
|
||||
from the list.
|
||||
.SH SINGLY-LINKED LIST EXAMPLE
|
||||
.nf
|
||||
SLIST_HEAD(slisthead, entry) head;
|
||||
struct slisthead *headp; /* Singly-linked List head. */
|
||||
struct entry {
|
||||
...
|
||||
SLIST_ENTRY(entry) entries; /* Singly-linked List. */
|
||||
...
|
||||
} *n1, *n2, *n3, *np;
|
||||
|
||||
SLIST_INIT(&head); /* Initialize the list. */
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
|
||||
SLIST_INSERT_HEAD(&head, n1, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert after. */
|
||||
SLIST_INSERT_AFTER(n1, n2, entries);
|
||||
|
||||
SLIST_REMOVE(&head, n2, entry, entries);/* Deletion. */
|
||||
free(n2);
|
||||
|
||||
n3 = head.slh_first;
|
||||
SLIST_REMOVE_HEAD(&head, entries); /* Deletion. */
|
||||
free(n3);
|
||||
|
||||
/* Forward traversal. */
|
||||
for (np = head.slh_first; np != NULL; np = np->entries.sle_next)
|
||||
np-> ...
|
||||
|
||||
while (head.slh_first != NULL) { /* List Deletion. */
|
||||
n1 = head.slh_first;
|
||||
SLIST_REMOVE_HEAD(&head, entries);
|
||||
free(n1);
|
||||
}
|
||||
.fi
|
||||
.SH SINGLY-LINKED TAIL QUEUES
|
||||
A singly-linked tail queue is headed by a structure defined by the
|
||||
.BR STAILQ_HEAD
|
||||
macro.
|
||||
This structure contains a pair of pointers,
|
||||
one to the first element in the tail queue and the other to
|
||||
the last element in the tail queue.
|
||||
The elements are singly linked for minimum space and pointer
|
||||
manipulation overhead at the expense of O(n) removal for arbitrary
|
||||
elements.
|
||||
New elements can be added to the tail queue after an existing element,
|
||||
at the head of the tail queue, or at the end of the tail queue.
|
||||
A
|
||||
.I STAILQ_HEAD
|
||||
structure is declared as follows:
|
||||
.RS
|
||||
.sp
|
||||
STAILQ_HEAD(HEADNAME, TYPE) head;
|
||||
.sp
|
||||
.RE
|
||||
where
|
||||
.BR HEADNAME
|
||||
is the name of the structure to be defined, and
|
||||
.BR TYPE
|
||||
is the type of the elements to be linked into the tail queue.
|
||||
A pointer to the head of the tail queue can later be declared as:
|
||||
.RS
|
||||
.sp
|
||||
struct HEADNAME *headp;
|
||||
.sp
|
||||
.RE
|
||||
(The names
|
||||
.IR head
|
||||
and
|
||||
.IR headp
|
||||
are user selectable.)
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_ENTRY
|
||||
declares a structure that connects the elements in
|
||||
the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_INIT
|
||||
initializes the tail queue referenced by
|
||||
.IR head .
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_INSERT_HEAD
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the head of the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_INSERT_TAIL
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the end of the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_INSERT_AFTER
|
||||
inserts the new element
|
||||
.I elm
|
||||
after the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_REMOVE_HEAD
|
||||
removes the element
|
||||
.I elm
|
||||
from the head of the tail queue.
|
||||
For optimum efficiency,
|
||||
elements being removed from the head of the tail queue should
|
||||
use this macro explicitly rather than the generic
|
||||
.I STAILQ_REMOVE
|
||||
macro.
|
||||
.LP
|
||||
The macro
|
||||
.BR STAILQ_REMOVE
|
||||
removes the element
|
||||
.I elm
|
||||
from the tail queue.
|
||||
.SH SINGLY-LINKED TAIL QUEUE EXAMPLE
|
||||
.nf
|
||||
STAILQ_HEAD(stailhead, entry) head;
|
||||
struct stailhead *headp; /* Singly-linked tail queue head. */
|
||||
struct entry {
|
||||
...
|
||||
STAILQ_ENTRY(entry) entries; /* Tail queue. */
|
||||
...
|
||||
} *n1, *n2, *n3, *np;
|
||||
|
||||
STAILQ_INIT(&head); /* Initialize the queue. */
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
|
||||
STAILQ_INSERT_HEAD(&head, n1, entries);
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
|
||||
STAILQ_INSERT_TAIL(&head, n1, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert after. */
|
||||
STAILQ_INSERT_AFTER(&head, n1, n2, entries);
|
||||
|
||||
/* Deletion. */
|
||||
STAILQ_REMOVE(&head, n2, entry, entries);
|
||||
free(n2);
|
||||
|
||||
/* Deletion from the head */
|
||||
n3 = head.stqh_first;
|
||||
STAILQ_REMOVE_HEAD(&head, entries);
|
||||
free(n3);
|
||||
|
||||
/* Forward traversal. */
|
||||
for (np = head.stqh_first; np != NULL; np = np->entries.stqe_next)
|
||||
np-> ...
|
||||
/* TailQ Deletion. */
|
||||
while (head.stqh_first != NULL) {
|
||||
n1 = head.stqh_first;
|
||||
TAILQ_REMOVE_HEAD(&head, entries);
|
||||
free(n1);
|
||||
}
|
||||
/* Faster TailQ Deletion. */
|
||||
n1 = head.stqh_first;
|
||||
while (n1 != NULL) {
|
||||
n2 = n1->entries.stqe_next;
|
||||
free(n1);
|
||||
n1 = n2;
|
||||
}
|
||||
STAILQ_INIT(&head);
|
||||
.fi
|
||||
.SH LISTS
|
||||
A list is headed by a structure defined by the
|
||||
.BR LIST_HEAD
|
||||
macro.
|
||||
This structure contains a single pointer to the first element
|
||||
on the list.
|
||||
The elements are doubly linked so that an arbitrary element can be
|
||||
removed without traversing the list.
|
||||
New elements can be added to the list after an existing element,
|
||||
before an existing element, or at the head of the list.
|
||||
A
|
||||
.I LIST_HEAD
|
||||
structure is declared as follows:
|
||||
.RS
|
||||
.sp
|
||||
LIST_HEAD(HEADNAME, TYPE) head;
|
||||
.sp
|
||||
.RE
|
||||
where
|
||||
.I HEADNAME
|
||||
is the name of the structure to be defined, and
|
||||
.I TYPE
|
||||
is the type of the elements to be linked into the list.
|
||||
A pointer to the head of the list can later be declared as:
|
||||
.RS
|
||||
.sp
|
||||
struct HEADNAME *headp;
|
||||
.sp
|
||||
.RE
|
||||
(The names
|
||||
.IR head
|
||||
and
|
||||
.IR headp
|
||||
are user selectable.)
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_ENTRY
|
||||
declares a structure that connects the elements in
|
||||
the list.
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_INIT
|
||||
initializes the list referenced by
|
||||
.IR head .
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_INSERT_HEAD
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the head of the list.
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_INSERT_AFTER
|
||||
inserts the new element
|
||||
.I elm
|
||||
after the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_INSERT_BEFORE
|
||||
inserts the new element
|
||||
.I elm
|
||||
before the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR LIST_REMOVE
|
||||
removes the element
|
||||
.I elm
|
||||
from the list.
|
||||
.SH LIST EXAMPLE
|
||||
.nf
|
||||
LIST_HEAD(listhead, entry) head;
|
||||
struct listhead *headp; /* List head. */
|
||||
struct entry {
|
||||
...
|
||||
LIST_ENTRY(entry) entries; /* List. */
|
||||
...
|
||||
} *n1, *n2, *n3, *np;
|
||||
|
||||
LIST_INIT(&head); /* Initialize the list. */
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
|
||||
LIST_INSERT_HEAD(&head, n1, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert after. */
|
||||
LIST_INSERT_AFTER(n1, n2, entries);
|
||||
|
||||
n3 = malloc(sizeof(struct entry)); /* Insert before. */
|
||||
LIST_INSERT_BEFORE(n2, n3, entries);
|
||||
|
||||
LIST_REMOVE(n2, entries); /* Deletion. */
|
||||
free(n2);
|
||||
|
||||
/* Forward traversal. */
|
||||
for (np = head.lh_first; np != NULL; np = np->entries.le_next)
|
||||
np-> ...
|
||||
|
||||
while (head.lh_first != NULL) { /* List Deletion. */
|
||||
n1 = head.lh_first;
|
||||
LIST_REMOVE(n1, entries);
|
||||
free(n1);
|
||||
}
|
||||
|
||||
n1 = head.lh_first; /* Faster List Delete. */
|
||||
while (n1 != NULL) {
|
||||
n2 = n1->entires.le_next;
|
||||
free(n1);
|
||||
n1 = n2;
|
||||
}
|
||||
LIST_INIT(&head);
|
||||
.fi
|
||||
.SH TAIL QUEUES
|
||||
A tail queue is headed by a structure defined by the
|
||||
.BR TAILQ_HEAD
|
||||
macro.
|
||||
This structure contains a pair of pointers,
|
||||
one to the first element in the tail queue and the other to
|
||||
the last element in the tail queue.
|
||||
The elements are doubly linked so that an arbitrary element can be
|
||||
removed without traversing the tail queue.
|
||||
New elements can be added to the tail queue after an existing element,
|
||||
before an existing element, at the head of the tail queue,
|
||||
or at the end of the tail queue.
|
||||
A
|
||||
.I TAILQ_HEAD
|
||||
structure is declared as follows:
|
||||
.RS
|
||||
.sp
|
||||
TAILQ_HEAD(HEADNAME, TYPE) head;
|
||||
.sp
|
||||
.RE
|
||||
where
|
||||
.BR HEADNAME
|
||||
is the name of the structure to be defined, and
|
||||
.BR TYPE
|
||||
is the type of the elements to be linked into the tail queue.
|
||||
A pointer to the head of the tail queue can later be declared as:
|
||||
.RS
|
||||
.sp
|
||||
struct HEADNAME *headp;
|
||||
.sp
|
||||
.RE
|
||||
(The names
|
||||
.IR head
|
||||
and
|
||||
.IR headp
|
||||
are user selectable.)
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_ENTRY
|
||||
declares a structure that connects the elements in
|
||||
the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_INIT
|
||||
initializes the tail queue referenced by
|
||||
.IR head .
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_INSERT_HEAD
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the head of the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_INSERT_TAIL
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the end of the tail queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_INSERT_AFTER
|
||||
inserts the new element
|
||||
.I elm
|
||||
after the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_INSERT_BEFORE
|
||||
inserts the new element
|
||||
.I elm
|
||||
before the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR TAILQ_REMOVE
|
||||
removes the element
|
||||
.I elm
|
||||
from the tail queue.
|
||||
.SH TAIL QUEUE EXAMPLE
|
||||
.nf
|
||||
TAILQ_HEAD(tailhead, entry) head;
|
||||
struct tailhead *headp; /* Tail queue head. */
|
||||
struct entry {
|
||||
...
|
||||
TAILQ_ENTRY(entry) entries; /* Tail queue. */
|
||||
...
|
||||
} *n1, *n2, *n3, *np;
|
||||
|
||||
TAILQ_INIT(&head); /* Initialize the queue. */
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
|
||||
TAILQ_INSERT_HEAD(&head, n1, entries);
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
|
||||
TAILQ_INSERT_TAIL(&head, n1, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert after. */
|
||||
TAILQ_INSERT_AFTER(&head, n1, n2, entries);
|
||||
|
||||
n3 = malloc(sizeof(struct entry)); /* Insert before. */
|
||||
TAILQ_INSERT_BEFORE(n2, n3, entries);
|
||||
|
||||
TAILQ_REMOVE(&head, n2, entries); /* Deletion. */
|
||||
free(n2);
|
||||
/* Forward traversal. */
|
||||
for (np = head.tqh_first; np != NULL; np = np->entries.tqe_next)
|
||||
np-> ...
|
||||
/* TailQ Deletion. */
|
||||
while (head.tqh_first != NULL) {
|
||||
n1 = head.tqh_first;
|
||||
TAILQ_REMOVE(&head, head.tqh_first, entries);
|
||||
free(n1);
|
||||
}
|
||||
/* Faster TailQ Deletion. */
|
||||
n1 = head.tqh_first;
|
||||
while (n1 != NULL) {
|
||||
n2 = n1->entries.tqe_next;
|
||||
free(n1);
|
||||
n1 = n2;
|
||||
}
|
||||
TAILQ_INIT(&head);
|
||||
.fi
|
||||
.SH CIRCULAR QUEUES
|
||||
A circular queue is headed by a structure defined by the
|
||||
.BR CIRCLEQ_HEAD
|
||||
macro.
|
||||
This structure contains a pair of pointers,
|
||||
one to the first element in the circular queue and the other to the
|
||||
last element in the circular queue.
|
||||
The elements are doubly linked so that an arbitrary element can be
|
||||
removed without traversing the queue.
|
||||
New elements can be added to the queue after an existing element,
|
||||
before an existing element, at the head of the queue, or at the end
|
||||
of the queue.
|
||||
A
|
||||
.I CIRCLEQ_HEAD
|
||||
structure is declared as follows:
|
||||
.RS
|
||||
.sp
|
||||
CIRCLEQ_HEAD(HEADNAME, TYPE) head;
|
||||
.sp
|
||||
.RE
|
||||
where
|
||||
.BR HEADNAME
|
||||
is the name of the structure to be defined, and
|
||||
.BR TYPE
|
||||
is the type of the elements to be linked into the circular queue.
|
||||
A pointer to the head of the circular queue can later be declared as:
|
||||
.RS
|
||||
.sp
|
||||
struct HEADNAME *headp;
|
||||
.sp
|
||||
.RE
|
||||
(The names
|
||||
.IR head
|
||||
and
|
||||
.IR headp
|
||||
are user selectable.)
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_ENTRY
|
||||
declares a structure that connects the elements in
|
||||
the circular queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_INIT
|
||||
initializes the circular queue referenced by
|
||||
.IR head .
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_INSERT_HEAD
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the head of the circular queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_INSERT_TAIL
|
||||
inserts the new element
|
||||
.I elm
|
||||
at the end of the circular queue.
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_INSERT_AFTER
|
||||
inserts the new element
|
||||
.I elm
|
||||
after the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_INSERT_BEFORE
|
||||
inserts the new element
|
||||
.I elm
|
||||
before the element
|
||||
.IR listelm .
|
||||
.LP
|
||||
The macro
|
||||
.BR CIRCLEQ_REMOVE
|
||||
removes the element
|
||||
.I elm
|
||||
from the circular queue.
|
||||
.SH CIRCULAR QUEUE EXAMPLE
|
||||
.nf
|
||||
CIRCLEQ_HEAD(circleq, entry) head;
|
||||
struct circleq *headp; /* Circular queue head. */
|
||||
struct entry {
|
||||
...
|
||||
CIRCLEQ_ENTRY entries; /* Circular queue. */
|
||||
...
|
||||
} *n1, *n2, *np;
|
||||
|
||||
CIRCLEQ_INIT(&head); /* Initialize the circular queue. */
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
|
||||
CIRCLEQ_INSERT_HEAD(&head, n1, entries);
|
||||
|
||||
n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
|
||||
CIRCLEQ_INSERT_TAIL(&head, n1, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert after. */
|
||||
CIRCLEQ_INSERT_AFTER(&head, n1, n2, entries);
|
||||
|
||||
n2 = malloc(sizeof(struct entry)); /* Insert before. */
|
||||
CIRCLEQ_INSERT_BEFORE(&head, n1, n2, entries);
|
||||
|
||||
CIRCLEQ_REMOVE(&head, n1, entries); /* Deletion. */
|
||||
free(n1);
|
||||
/* Forward traversal. */
|
||||
for (np = head.cqh_first; np != (void *)&head; np = np->entries.cqe_next)
|
||||
np-> ...
|
||||
/* Reverse traversal. */
|
||||
for (np = head.cqh_last; np != (void *)&head; np = np->entries.cqe_prev)
|
||||
np-> ...
|
||||
/* CircleQ Deletion. */
|
||||
while (head.cqh_first != (void *)&head) {
|
||||
n1 = head.cqh_first;
|
||||
CIRCLEQ_REMOVE(&head, head.cqh_first, entries);
|
||||
free(n1);
|
||||
}
|
||||
/* Faster CircleQ Deletion. */
|
||||
n1 = head.cqh_first;
|
||||
while (n1 != (void *)&head) {
|
||||
n2 = n1->entries.cqh_next;
|
||||
free(n1);
|
||||
n1 = n2;
|
||||
}
|
||||
CIRCLEQ_INIT(&head);
|
||||
.fi
|
||||
.SH HISTORY
|
||||
The
|
||||
.BR queue
|
||||
functions first appeared in 4.4BSD.
|
||||
Loading…
x
Reference in New Issue
Block a user