.\"
.\" Copyright (c) 1993 Michael Haardt (michael@moria.de),
.\"   Fri Apr  2 11:32:09 MET DST 1993
.\"
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
.\" License along with this manual; if not, write to the Free
.\" Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111,
.\" USA.
.\"
.\" Tue Jul  6 12:42:46 MDT 1993 <dminer@nyx.cs.du.edu>
.\" Added "Calling Directly" and supporting paragraphs
.\"
.\" Modified Sat Jul 24 15:19:12 1993 by Rik Faith <faith@cs.unc.edu>
.\"
.\" Modified 21 Aug 1994 by Michael Chastain <mec@shell.portal.com>:
.\"   Added explanation of arg stacking when 6 or more args.
.\"
.\" Modified 10 June 1995 by Andries Brouwer <aeb@cwi.nl>
.\"
.\" Japanese Version Copyright (c) 1997 KUNIMOTO Yasuhiro, all rights reserved.
.\" Translated Jun 27, 1997 by KUNIMOTO Yasuhiro (hiro@kthree.co.jp)
.\"
.\" Modified  Jul  5, 1997 by Yoshiki Sugiura (yox@in.aix.or.jp)
.\" Modified  Jul  6, 1997 by Yoshiki Sugiura (yox@in.aix.or.jp)
.\" Modified Sun Mar 21 17:24:08 JST 1999
.\"         by HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified Mon Jan  3 18:17:22 JST 2000
.\"         by Kentaro Shirakata <argrath@yo.rim.or.jp>
.\"
.TH INTRO 2 "22 May 1996" "Linux 1.2.13" "Linux Programmer's Manual"
.SH ̾
intro \- ƥॳ
.SH 
ξϤ Linux Υƥॳ򵭽ҤƤ롣
Linux 2.0 Ǥ 164 ĤΥƥॳ뤬¸ߤ롣
.SS "ľܸƤӽФ"
ۤȤɤξ硢ľܥƥॳƤӽФɬפϤʤ
ˤäƤɸ C 饤֥ɬפʴؿ
ʤ⤷ʤ
.SS ""
.B #include <linux/unistd.h>

A _syscall macro

desired system call

.SS 
ƥॳ˴ؤƤΥץȥפΤ뤳Ȥפ
롣θĿη֤ͤηΤʤФʤʤ
ºݤλѤˤäƤϡưפ˥ƥƤӽФ˼ 6 Ĥ
ޥѰդƤ롣ηϰʲ̤Ǥ:
.sp
.RS
.RI _syscall X ( type , name , type1 , arg1 , type2 , arg2 ,...)
.RS
.HP
 \fIX\fP  0\(en5 ǥƥॳ뤬ɬפȤοǤ롣
.HP
\fItype\fP ϥƥॳ֤ͤηǤ롣
.HP
\fIname\fP ϥƥॳ̾Ǥ롣
.HP
\fItypeN\fP  N ܤΰηǤ롣
.HP
\fIargN\fP  N ܤΰ̾Ǥ롣
.RE
.RE
.sp
Υޥϻꤷ \fI̾\fP Ĵؿ롣
öեˤ _syscall() ޥƳȡ
\fI̾\fP ˤäƤΥƥॳƤ֤ȤǤ롣
.SH 
.nf
.sp
#include <stdio.h>
#include <linux/unistd.h>	/* for _syscallX macros/related stuff */
#include <linux/kernel.h>	/* for struct sysinfo */

_syscall1(int, sysinfo, struct sysinfo *, info);

/* ա nroff Υե뤫ľܥԡȤ 
printf ʸ˴ޤޤƤ;ʬʥХåå
Ȥ˺ʤ褦 */

int main(void)
{
	struct sysinfo s_info;
	int error;

	error = sysinfo(&s_info);
	printf("code error = %d\\n", error);
        printf("Uptime = %ds\\nLoad: 1 min %d / 5 min %d / 15 min %d\\n"
                "RAM: total %d / free %d / shared %d\\n"
                "Memory in buffers = %d\\nSwap: total %d / free %d\\n"
                "Number of processes = %d\\n",
		s_info.uptime, s_info.loads[0],
		s_info.loads[1], s_info.loads[2],
		s_info.totalram, s_info.freeram,
		s_info.sharedram, s_info.bufferram,
		s_info.totalswap, s_info.freeswap,
		s_info.procs);
	return(0);
}
.fi
.SH 
.nf
code error = 0
uptime = 502034s
Load: 1 min 13376 / 5 min 5504 / 15 min 1152
RAM: total 15343616 / free 827392 / shared 8237056
Memory in buffers = 5066752
Swap: total 27881472 / free 24698880
Number of processes = 40
.fi
.SH 
_syscall()ޥϥץȥפʤ桼ϼʬ
ץȥפ񤫤ʤФʤʤ⤷ʤ 
C++ 桼ξä˽פǤ롣
.sp
ƥॳΥ顼ɤΤߤޤΥ顼ɤΤߤ
֤ȤƤ櫓ǤϤʤ
Υƥॳ뤬ɤΤ褦ʥ顼ɤ֤ˤĤƳǧ
ˤϤΥɤɤɬפ롣
Ƥξ硢ɸΥ顼ɤ˴ؤƤ(㤨 \-\fBEPERM\fP Τ褦)
֤ͤ
_syscall() ޥϤΥƥॳ֤ \fIr\fP Ǥʤ硢
ͤ򤽤Τޤ֤ξˤѿ
.I errno
 \-\fIr\fP ꤷ \-1 ֤
ƥ顼ɤ˴ؤƤ
.BR errno (3)
򻲾ȡ
.sp
ĤΥƥॳ (㤨
.BR mmap 
ʤ)  5 İʾΰ׵᤹롣
äƥॳϥå˰ץå夷
ΰΤޤؤΥݥ󥿤Ϥƽ롣
.sp
ƥॳ硢ΰηϤ(by-value)Ǥ뤫
(¤ΤΤ褦ʽŪʥǡξ)ݥϤ(by-pointer)
ǤʤФʤʤ
.SH 
ξϤǤϡʲΤ褦ʴĤά͡ Unix Υפؼ
뤿˻Ѥ롣
.TP
SVr4
"Programmer's Reference Manual: Operating System API 
(Intel processors)" (Prentice-Hall1992, ISBN 0-13-951294-2) 
ҤƤ System V Release 4 Unix
.TP
SVID
System V Interface Definition
"The System V Interface Definition, Fourth Edition" 
ҤƤ롣
.TP
POSIX.1
IEEE 1003.1-1990 part 1̾ ISO/IEC 9945-1:1990s
Donald Lewine  "POSIX Programmer's Guide"
(O'Reilly & Associates,Inc., 1991, ISBN 0-937175-73-0)˵ҤƤ
"IEEE Portable Operating System Interface for Computing Environments"
ˤ⤬롣
.TP
POSIX.1b
IEEE Std 1003.1b-1993 (POSIX.1b standard) ΰܿǽʥڥ졼ƥ
ƥΤΥꥢ륿ൡ̾ ISO/IEC 9945-1:1996
Bill O. Gallmeister 
"Programming for the real world \- POSIX.4"
(O'Reilly & Associates, Inc. ISBN1-56592-074-0)
ˤ⤬롣
.TP
SUS, SUSv2
Single Unix Specification.
(X/Open  The Open Group ˤäƺ줿
http://www.UNIX-systems.org/version2/ ⻲ȤΤȡ)
.TP
4.3BSD/4.4BSD
Berkeley Unix 4.3  4.4 ǥȥӥ塼
4.4BSD  4.3 Фƾ̸ߴǤ롣
.TP
V7
٥븦ͳ褹븵 UnixǤ Version 7
.SH ե
.I /usr/include/linux/unistd.h
.SH Ϣ
.BR errno (3)