+.\" Copyright (C) 2006 Michael Kerrisk
+.\" and Copyright (C) 2008 Linux Foundation, written by Michael Kerrisk
+.\" <mtk.manpages@gmail.com>
+.\"
+.\" Permission is granted to make and distribute verbatim copies of this
+.\" manual provided the copyright notice and this permission notice are
+.\" preserved on all copies.
+.\"
+.\" Permission is granted to copy and distribute modified versions of this
+.\" manual under the conditions for verbatim copying, provided that the
+.\" entire resulting derived work is distributed under the terms of a
+.\" permission notice identical to this one.
+.\"
+.\" Since the Linux kernel and libraries are constantly changing, this
+.\" manual page may be incorrect or out-of-date. The author(s) assume no
+.\" responsibility for errors or omissions, or for damages resulting from
+.\" the use of the information contained herein. The author(s) may not
+.\" have taken the same level of care in the production of this manual,
+.\" which is licensed free of charge, as they might when working
+.\" professionally.
+.\"
+.\" Formatted or processed versions of this manual, if unaccompanied by
+.\" the source, must acknowledge the copyright and authors of this work.
+.\"
+.\"*******************************************************************
+.\"
+.\" This file was generated with po4a. Translate the source file.
+.\"
+.\"*******************************************************************
+.TH CPU_SET 3 2012\-03\-15 Linux "Linux Programmer's Manual"
+.SH 名前
+CPU_SET, CPU_CLR, CPU_ISSET, CPU_ZERO, CPU_COUNT, CPU_AND, CPU_OR, CPU_XOR,
+CPU_EQUAL, CPU_ALLOC, CPU_ALLOC_SIZE, CPU_FREE, CPU_SET_S, CPU_CLR_S,
+CPU_ISSET_S, CPU_ZERO_S, CPU_COUNT_S, CPU_AND_S, CPU_OR_S, CPU_XOR_S,
+CPU_EQUAL_S \- macros for manipulating CPU sets
+.SH 書式
+.nf
+\fB#define _GNU_SOURCE\fP /* feature_test_macros(7) 参照 */
+\fB#include <sched.h>\fP
+.sp
+\fBvoid CPU_ZERO(cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBvoid CPU_SET(int \fP\fIcpu\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+\fBvoid CPU_CLR(int \fP\fIcpu\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+\fBint CPU_ISSET(int \fP\fIcpu\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBint CPU_COUNT(cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBvoid CPU_AND(cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+\fBvoid CPU_OR(cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+\fBvoid CPU_XOR(cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+.sp
+\fBint CPU_EQUAL(cpu_set_t *\fP\fIset1\fP\fB, cpu_set_t *\fP\fIset2\fP\fB);\fP
+.sp
+\fBcpu_set_t *CPU_ALLOC(int \fP\fInum_cpus\fP\fB);\fP
+\fBvoid CPU_FREE(cpu_set_t *\fP\fIset\fP\fB);\fP
+\fBsize_t CPU_ALLOC_SIZE(int \fP\fInum_cpus\fP\fB);\fP
+.sp
+\fBvoid CPU_ZERO_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBvoid CPU_SET_S(int \fP\fIcpu\fP\fB, size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+\fBvoid CPU_CLR_S(int \fP\fIcpu\fP\fB, size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+\fBint CPU_ISSET_S(int \fP\fIcpu\fP\fB, size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBint CPU_COUNT_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset\fP\fB);\fP
+.sp
+\fBvoid CPU_AND_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+\fBvoid CPU_OR_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+\fBvoid CPU_XOR_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIdestset\fP\fB,\fP
+\fB cpu_set_t *\fP\fIsrcset1\fP\fB, cpu_set_t *\fP\fIsrcset2\fP\fB);\fP
+.sp
+\fBint CPU_EQUAL_S(size_t \fP\fIsetsize\fP\fB, cpu_set_t *\fP\fIset1\fP\fB, cpu_set_t *\fP\fIset2\fP\fB);\fP
+.fi
+.SH 説明
+The \fIcpu_set_t\fP data structure represents a set of CPUs. CPU sets are used
+by \fBsched_setaffinity\fP(2) and similar interfaces.
+
+The \fIcpu_set_t\fP data type is implemented as a bitset. However, the data
+structure treated as considered opaque: all manipulation of CPU sets should
+be done via the macros described in this page.
+
+The following macros are provided to operate on the CPU set \fIset\fP:
+.TP 17
+\fBCPU_ZERO\fP()
+Clears \fIset\fP, so that it contains no CPUs.
+.TP
+\fBCPU_SET\fP()
+Add CPU \fIcpu\fP to \fIset\fP.
+.TP
+\fBCPU_CLR\fP()
+Remove CPU \fIcpu\fP from \fIset\fP.
+.TP
+\fBCPU_ISSET\fP()
+Test to see if CPU \fIcpu\fP is a member of \fIset\fP.
+.TP
+\fBCPU_COUNT\fP()
+Return the number of CPUs in \fIset\fP.
+.PP
+Where a \fIcpu\fP argument is specified, it should not produce side effects,
+since the above macros may evaluate the argument more than once.
+.PP
+The first available CPU on the system corresponds to a \fIcpu\fP value of 0,
+the next CPU corresponds to a \fIcpu\fP value of 1, and so on. The constant
+\fBCPU_SETSIZE\fP (currently 1024) specifies a value one greater than the
+maximum CPU number that can be stored in \fIcpu_set_t\fP.
+
+The following macros perform logical operations on CPU sets:
+.TP 17
+\fBCPU_AND\fP()
+Store the intersection of the sets \fIsrcset1\fP and \fIsrcset2\fP in \fIdestset\fP
+(which may be one of the source sets).
+.TP
+\fBCPU_OR\fP()
+Store the union of the sets \fIsrcset1\fP and \fIsrcset2\fP in \fIdestset\fP (which
+may be one of the source sets).
+.TP
+\fBCPU_XOR\fP()
+Store the XOR of the sets \fIsrcset1\fP and \fIsrcset2\fP in \fIdestset\fP (which may
+be one of the source sets). The XOR means the set of CPUs that are in
+either \fIsrcset1\fP or \fIsrcset2\fP, but not both.
+.TP
+\fBCPU_EQUAL\fP()
+Test whether two CPU set contain exactly the same CPUs.
+.SS "Dynamically sized CPU sets"
+Because some applications may require the ability to dynamically size CPU
+sets (e.g., to allocate sets larger than that defined by the standard
+\fIcpu_set_t\fP data type), glibc nowadays provides a set of macros to support
+this.
+
+The following macros are used to allocate and deallocate CPU sets:
+.TP 17
+\fBCPU_ALLOC\fP()
+Allocate a CPU set large enough to hold CPUs in the range 0 to
+\fInum_cpus\-1\fP.
+.TP
+\fBCPU_ALLOC_SIZE\fP()
+Return the size in bytes of the CPU set that would be needed to hold CPUs in
+the range 0 to \fInum_cpus\-1\fP. This macro provides the value that can be
+used for the \fIsetsize\fP argument in the \fBCPU_*_S\fP() macros described
+below.
+.TP
+\fBCPU_FREE\fP()
+Free a CPU set previously allocated by \fBCPU_ALLOC\fP().
+.PP
+The macros whose names end with "_S" are the analogs of the similarly named
+macros without the suffix. These macros perform the same tasks as their
+analogs, but operate on the dynamically allocated CPU set(s) whose size is
+\fIsetsize\fP bytes.
+.SH 返り値
+\fBCPU_ISSET\fP() and \fBCPU_ISSET_S\fP() return nonzero if \fIcpu\fP is in \fIset\fP;
+otherwise, it returns 0.
+
+\fBCPU_COUNT\fP() and \fBCPU_COUNT_S\fP() return the number of CPUs in \fIset\fP.
+
+\fBCPU_EQUAL\fP() and \fBCPU_EQUAL_S\fP() return nonzero if the two CPU sets are
+equal; otherwise it returns 0.
+
+\fBCPU_ALLOC\fP() returns a pointer on success, or NULL on failure. (Errors
+are as for \fBmalloc\fP(3).)
+
+\fBCPU_ALLOC_SIZE\fP() returns the number of bytes required to store a CPU set
+of the specified cardinality.
+
+The other functions do not return a value.
+.SH バージョン
+The \fBCPU_ZERO\fP(), \fBCPU_SET\fP(), \fBCPU_CLR\fP(), and \fBCPU_ISSET\fP() macros
+were added in glibc 2.3.3.
+
+\fBCPU_COUNT\fP() first appeared in glibc 2.6.
+
+\fBCPU_AND\fP(), \fBCPU_OR\fP(), \fBCPU_XOR\fP(), \fBCPU_EQUAL\fP(), \fBCPU_ALLOC\fP(),
+\fBCPU_ALLOC_SIZE\fP(), \fBCPU_FREE\fP(), \fBCPU_ZERO_S\fP(), \fBCPU_SET_S\fP(),
+\fBCPU_CLR_S\fP(), \fBCPU_ISSET_S\fP(), \fBCPU_AND_S\fP(), \fBCPU_OR_S\fP(),
+\fBCPU_XOR_S\fP(), and \fBCPU_EQUAL_S\fP() first appeared in glibc 2.7.
+.SH 準拠
+These interfaces are Linux\-specific.
+.SH 注意
+To duplicate a CPU set, use \fBmemcpy\fP(3).
+
+Since CPU sets are bitsets allocated in units of long words, the actual
+number of CPUs in a dynamically allocated CPU set will be rounded up to the
+next multiple of \fIsizeof(unsigned long)\fP. An application should consider
+the contents of these extra bits to be undefined.
+
+Notwithstanding the similarity in the names, note that the constant
+\fBCPU_SETSIZE\fP indicates the number of CPUs in the \fIcpu_set_t\fP data type
+(thus, it is effectively a count of bits in the bitset), while the
+\fIsetsize\fP argument of the \fBCPU_*_S\fP() macros is a size in bytes.
+
+The data types for arguments and return values shown in the SYNOPSIS are
+hints what about is expected in each case. However, since these interfaces
+are implemented as macros, the compiler won't necessarily catch all type
+errors if you violate the suggestions.
+.SH バグ
+.\" http://sourceware.org/bugzilla/show_bug.cgi?id=7029
+On 32\-bit platforms with glibc 2.8 and earlier, \fBCPU_ALLOC\fP() allocates
+twice as much space as is required, and \fBCPU_ALLOC_SIZE\fP() returns a value
+twice as large as it should. This bug should not affect the semantics of a
+program, but does result in wasted memory and less efficient operation of
+the macros that operate on dynamically allocated CPU sets. These bugs are
+fixed in glibc 2.9.
+.SH EXAMPLE
+The following program demonstrates the use of some of the macros used for
+dynamically allocated CPU sets.
+
+.nf
+#define _GNU_SOURCE
+#include <sched.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <assert.h>
+
+int
+main(int argc, char *argv[])
+{
+ cpu_set_t *cpusetp;
+ size_t size;
+ int num_cpus, cpu;
+
+ if (argc < 2) {
+ fprintf(stderr, "Usage: %s <num\-cpus>\en", argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
+ num_cpus = atoi(argv[1]);
+
+ cpusetp = CPU_ALLOC(num_cpus);
+ if (cpusetp == NULL) {
+ perror("CPU_ALLOC");
+ exit(EXIT_FAILURE);
+ }
+
+ size = CPU_ALLOC_SIZE(num_cpus);
+
+ CPU_ZERO_S(size, cpusetp);
+ for (cpu = 0; cpu < num_cpus; cpu += 2)
+ CPU_SET_S(cpu, size, cpusetp);
+
+ printf("CPU_COUNT() of set: %d\en", CPU_COUNT_S(size, cpusetp));
+
+ CPU_FREE(cpusetp);
+ exit(EXIT_SUCCESS);
+}
+.fi
+.SH 関連項目
+\fBsched_setaffinity\fP(2), \fBpthread_attr_setaffinity_np\fP(3),
+\fBpthread_setaffinity_np\fP(3), \fBcpuset\fP(7)
+.SH この文書について
+この man ページは Linux \fIman\-pages\fP プロジェクトのリリース 3.40 の一部
+である。プロジェクトの説明とバグ報告に関する情報は
+http://www.kernel.org/doc/man\-pages/ に書かれている。
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