(split) LDP_man-pages: release ioctl.2 [JM:00378]

[linuxjm/LDP_man-pages.git] / draft / man3 / strtol.3

.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" 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.\" manual page may be incorrect or out-of-date.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.
.\"
.\" References consulted:
.\"     Linux libc source code
.\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
.\"     386BSD man pages
.\" Modified Sun Jul 25 10:53:39 1993 by Rik Faith (faith@cs.unc.edu)
.\" Added correction due to nsd@bbc.com (Nick Duffek) - aeb, 950610
.\"
.\" Japanese Version Copyright (c) 1999 AKAMATSU, Kazuo
.\"         all rights reserved.
.\" Translated Thu Jan 9 21:00:00 JST 1999
.\"         by AKAMATSU, Kazuo
.\" Updated Sun Apr  8 JST 2001 by Kentaro Shirakata <argrath@ub32.org>
.\" Updated Sat Mar 23 JST 2002 by Kentaro Shirakata <argrath@ub32.org>
.\" Updated & Modified 2006-07-20,
.\"         Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.36
.\"
.\" WORD:       base            ´ð¿ô
.\"
.TH STRTOL 3  2010-09-20 "GNU" "Linux Programmer's Manual"
.SH ̾Á°
.\"O strtol, strtoll, strtoq \- convert a string to a long integer
strtol, strtoll, strtoq \- ʸ»úÎó¤ò long int ¤ËÊÑ´¹¤¹¤ë
.SH ½ñ¼°
.nf
.B #include <stdlib.h>
.sp
.BI "long int strtol(const char *" nptr ", char **" endptr ", int " base );
.sp
.BI "long long int strtoll(const char *" nptr ", char **" endptr \
", int " base );
.fi
.sp
.in -4n
.\"O Feature Test Macro Requirements for glibc (see
.\"O .BR feature_test_macros (7)):
glibc ¸þ¤±¤Îµ¡Ç½¸¡ºº¥Þ¥¯¥í¤ÎÍ×·ï
.RB ( feature_test_macros (7)
»²¾È):
.in
.sp
.ad l
.BR strtoll ():
.RS 4
XOPEN_SOURCE\ >=\ 600 || _BSD_SOURCE || _SVID_SOURCE || _ISOC99_SOURCE ||
_POSIX_C_SOURCE\ >=\ 200112L;
.br
or
.I cc\ -std=c99
.RE
.ad
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O The
.\"O .BR strtol ()
.\"O function converts the initial part of the string
.\"O in \fInptr\fP to a long integer value according to the given \fIbase\fP,
.\"O which must be between 2 and 36 inclusive, or be the special value 0.
.BR strtol ()
´Ø¿ô¤Ï¡¢ \fInptr\fP ¤Îʸ»úÎó¤ÎºÇ½é¤ÎÉôʬ¤ò¡¢
\fIbase\fP ¤ò´ð¿ô¤È¤·¤Æ long int ¤ËÊÑ´¹¤¹¤ë¡£
¤³¤Î \fIbase\fP ¤Ï 2 ¤«¤é 36 ¤Þ¤Ç¤ÎÃÍ
¤¢¤ë¤¤¤ÏÆÃÊ̤ʰÕÌ£¤ò»ý¤ÄÃÍ 0 ¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.PP
.\"O The string may begin with an arbitrary amount of white space (as
.\"O determined by
.\"O .BR isspace (3))
.\"O followed by a single optional \(aq+\(aq or \(aq\-\(aq sign.
.\"O If \fIbase\fP is zero or 16, the string may then include a
.\"O "0x" prefix, and the number will be read in base 16; otherwise, a
.\"O zero \fIbase\fP is taken as 10 (decimal) unless the next character
.\"O is \(aq0\(aq, in which case it is taken as 8 (octal).
ʸ»úÎó¤ÎÀèƬ¤Ë¤Ï¡¢Ç¤°Õ¤Î¿ô¤Î¶õÇò¤¬¤¢¤Ã¤Æ¤â¤è¤¯ (¶õÇò¤Ï
.BR isspace (3)
¤ÇȽÄꤵ¤ì¤ë)¡¢¤Þ¤¿¿ô»ú¤ÎľÁ°¤Ë¤Ï \(aq+\(aq ¤« \(aq\-\(aq ¤Î
Éä¹æ¤¬¤¢¤Ã¤Æ¤â¤è¤¤¡£
\fIbase\fP ¤¬ 0 ¤Þ¤¿¤Ï 16 ¤Î¾ì¹ç¤Ë¤Ï¡¢Ê¸»úÎó¤ÎÀèƬ¤Ë "0x" ¤òÃÖ¤¯¤³¤È¤¬
¤Ç¤­¡¢¤½¤Î¾ì¹ç¤Ë¤Ïʸ»úÎó¤Ï 16¿Ê¿ô¤È¤·¤Æ°·¤ï¤ì¤ë¡£
¤³¤ì°Ê³°¤Îʸ»úÎó¤Ç \fIbase\fP ¤¬ 0 ¤Î¾ì¹ç¤Ï¡¢
ʸ»úÎó¤¬ \(aq0\(aq ¤Ç»Ï¤Þ¤ë¤È¤­¤Ï 8¿Ê¿ô¤È¤·¤Æ¡¢
¤½¤ì°Ê³°¤Î¤È¤­¤Ï 10¿Ê¿ô¤È¤·¤Æ°·¤ï¤ì¤ë¡£
.PP
.\"O The remainder of the string is converted to a
.\"O .I long int
.\"O value
.\"O in the obvious manner, stopping at the first character which is not a
.\"O valid digit in the given base.
.\"O (In bases above 10, the letter \(aqA\(aq in
.\"O either upper or lower case represents 10, \(aqB\(aq represents 11, and so
.\"O forth, with \(aqZ\(aq representing 35.)
¿ô»ú¤òɽ¤¹Ê¸»úÎó¤Ï
.I long int
¤ËÊÑ´¹¤µ¤ì¤ë¤¬¡¢´ð¿ô¤ËÂФ·¤Æ
Í­¸ú¤Ç¤Ê¤¤¿ô»ú¤¬¸½¤ì¤¿»þÅÀ¤ÇÊÑ´¹¤Ï½ªÎ»¤¹¤ë¡£(11¿Ê¿ô°Ê¾å¤Ç¤Ï \(aqA\(aq ¤Ï
Âçʸ»ú¡¦¾®Ê¸»ú¤Ë´Ø¤ï¤é¤º 10 ¤òɽ¤·¡¢ \(aqB\(aq ¤Ï 11 ¤òɽ¸½¤·¡¢
°Ê²¼Æ±Íͤˡ¢ \(aqZ\(aq ¤Ï 35 ¤òɽ¤¹¡£)
.PP
.\"O If \fIendptr\fP is not NULL,
.\"O .BR strtol ()
.\"O stores the address of the
.\"O first invalid character in \fI*endptr\fP.
.\"O If there were no digits at
.\"O all,
.\"O .BR strtol ()
.\"O stores the original value of \fInptr\fP in
.\"O \fI*endptr\fP (and returns 0).
\fIendptr\fP ¤¬¥Ì¥ëÃÍ (NULL) ¤Ç¤Ê¤¤¾ì¹ç¤Ï¡¢ºÇ½é¤Ë¸½¤ì¤¿ÉÔÀµ¤Êʸ»ú¤¬
.BR strtol ()
¤Ë¤è¤Ã¤Æ \fI*endptr\fP ¤ËÊݸ¤µ¤ì¤Æ¤¤¤ë¡£
ʸ»úÎó¤ËÍ­¸ú¤Ê¿ô»ú¤¬¤Ò¤È¤Ä¤â¤Ê¤±¤ì¤Ð¡¢
.BR strtol ()
¤Ï \fInptr\fP
¤Î¸µ¤ÎÃͤò \fI*endptr\fP ¤ËÂåÆþ¤¹¤ë (¤½¤·¤Æ 0 ¤òÊÖ¤¹)¡£
.\"O In particular, if \fI*nptr\fP is not \(aq\\0\(aq but \fI**endptr\fP
.\"O is \(aq\\0\(aq on return, the entire string is valid.
Æäˡ¢\fI*nptr\fP ¤¬ \(aq\\0\(aq °Ê³°¤Ç¡¢ÊÖ¤µ¤ì¤¿ \fI**endptr\fP ¤¬
\(aq\\0\(aq ¤Ê¤é¤Ð¡¢Ê¸»úÎóÁ´ÂΤ¬Í­¸ú¤À¤Ã¤¿¤³¤È¤Ë¤Ê¤ë¡£
.PP
.\"O The
.\"O .BR strtoll ()
.\"O function works just like the
.\"O .BR strtol ()
.\"O function but returns a long long integer value.
.BR strtoll ()
´Ø¿ô¤Ï
.BR strtol ()
¤ÈƱÍͤÀ¤¬¡¢long long int ·¿¤ÎÃͤòÊÖ¤¹¡£
.SH ÊÖ¤êÃÍ
.\"O The
.\"O .BR strtol ()
.\"O function returns the result of the conversion,
.\"O unless the value would underflow or overflow.
.\"O If an underflow occurs,
.\"O .BR strtol ()
.\"O returns
.\"O .BR LONG_MIN .
.\"O If an overflow occurs,
.\"O .BR strtol ()
.\"O returns
.\"O .BR LONG_MAX .
.\"O In both cases, \fIerrno\fP is set to
.\"O .BR ERANGE .
¥¢¥ó¥À¡¼¥Õ¥í¡¼¤â¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤âµ¯¤­¤Ê¤«¤Ã¤¿¾ì¹ç¡¢
.BR strtol ()
´Ø¿ô¤Ï
ÊÑ´¹¤µ¤ì¤¿ÃͤòÊÖ¤¹¡£¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤·¤¿¾ì¹ç¤Ë¤Ï
.B LONG_MAX
¤¬Ê֤ꡢ
¥¢¥ó¥À¡¼¥Õ¥í¡¼¤·¤¿¾ì¹ç¤Ë¤Ï
.B LONG_MIN
¤¬Ê֤롣¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¡¢
¥¢¥ó¥À¡¼¥Õ¥í¡¼¤Î¤¤¤º¤ì¤Î¾ì¹ç¤Ë¤â
Âç°èÊÑ¿ô \fIerrno\fP ¤Ë¤Ï
.B ERANGE
¤¬ÀßÄꤵ¤ì¤ë¡£
.\"O Precisely the same holds for
.\"O .BR strtoll ()
.\"O (with
.\"O .B LLONG_MIN
.\"O and
.\"O .B LLONG_MAX
.\"O instead of
.\"O .B LONG_MIN
.\"O and
.\"O .BR LONG_MAX ).
.BR strtoll ()
¤âƱÍͤǤ¢¤ë¤¬¡¢
.B LONG_MIN
¤È
.B LONG_MAX
¤ÎÂå¤ï¤ê¤Ë
.B LLONG_MIN
¤È
.B LLONG_MAX
¤¬ÊÖ¤µ¤ì¤ë¡£
.SH ¥¨¥é¡¼
.TP
.B EINVAL
.\"O (not in C99)
.\"O The given
.\"O .I base
.\"O contains an unsupported value.
(C99 ¤Ë¤Ï¤Ê¤¤)
.I base
¤¬Âбþ¤·¤Æ¤¤¤Ê¤¤ÃͤǤ¢¤ë¡£
.TP
.B ERANGE
.\"O The resulting value was out of range.
·ë²Ì¤ÎÃͤ¬Èϰϳ°¤Ç¤¢¤ë¡£
.LP
.\"O The implementation may also set \fIerrno\fP to \fBEINVAL\fP in case
.\"O no conversion was performed (no digits seen, and 0 returned).
¼ÂÁõ¤Ë¤è¤Ã¤Æ¤Ï¡¢ÊÑ´¹¤¬¹Ô¤ï¤ì¤Ê¤«¤Ã¤¿¾ì¹ç (¿ô»ú¤¬¤Ê¤¯¡¢0 ¤òÊÖ¤·¤¿¾ì¹ç)¡¢
\fIerrno\fP ¤Ë \fBEINVAL\fP ¤¬ÀßÄꤵ¤ì¤ë¾ì¹ç¤¬¤¢¤ë¡£
.SH ½àµò
.\"O .BR strtol ()
.\"O conforms to SVr4, 4.3BSD, C89, C99 and POSIX.1-2001, and
.\"O .BR strtoll ()
.\"O to C99 and POSIX.1-2001.
.BR strtol ()
¤Ï SVr4, 4.3BSD, C89, C99 ¤È POSIX.1-2001 ¤Ë½àµò¤·¤Æ¤¤¤ë¡£
.BR strtoll ()
¤Ï C99 ¤È POSIX.1-2001 ¤Ë½àµò¤·¤Æ¤¤¤ë¡£
.\"O .SH NOTES
.SH Ãí°Õ
.\"O Since
.\"O .BR strtol ()
.\"O can legitimately return 0,
.\"O .BR LONG_MAX ,
.\"O or
.\"O .B LONG_MIN
.\"O .RB ( LLONG_MAX
.\"O or
.\"O .B LLONG_MIN
.\"O for
.\"O .BR strtoll ())
.\"O on both success and failure, the calling program should set
.\"O .I errno
.\"O to 0 before the call,
.\"O and then determine if an error occurred by checking whether
.\"O .I errno
.\"O has a nonzero value after the call.
.B strtol ()
¤«¤é¤ÏÀ®¸ù¡¢¼ºÇԤɤÁ¤é¤Î¾ì¹ç¤Ç¤â
0,
.BR LONG_MAX ,
.B LONG_MIN
.RB ( strtoll ()
¤Ç¤Ï
.BR LLONG_MAX ,
.BR LLONG_MIN )
¤¬ÊÖ¤ë²ÄǽÀ­¤¬¤¢¤ë¤Î¤Ç¡¢
¥×¥í¥°¥é¥à¤Ï´Ø¿ô¤ò¸Æ¤Ó½Ð¤¹Á°¤Ë
.I errno
¤ò 0 ¤ËÀßÄꤷ¡¢¸Æ¤Ó½Ð¤·¸å¤Ë
.I errno
¤¬ 0 °Ê³°¤ÎÃͤ«¤É¤¦¤«¤ò³Îǧ¤·¥¨¥é¡¼¤¬È¯À¸¤·¤¿¤«¤É¤¦¤«¤òȽÃǤ¹¤ë
ɬÍפ¬¤¢¤ë¡£

.\"O In locales other than the "C" locale, other strings may also be accepted.
.\"O (For example, the thousands separator of the current locale may be
.\"O supported.)
"C" °Ê³°¤Î¥í¥±¡¼¥ë¤Î¾ì¹ç¡¢¤½¤Î¾¤Îʸ»úÎó¤â¼õ¤±ÉÕ¤±¤é¤ì¤ë¤«¤â¤·¤ì¤Ê¤¤¡£
(Î㤨¤Ð¡¢¸½ºß¤Î¥í¥±¡¼¥ë¤Î 1000 Ëè¤Î¶èÀÚ¤êʸ»ú¤¬¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤ë¤«¤â¤·¤ì¤Ê¤¤¡£)
.LP
.\"O BSD also has
BSD ¤Ë¤Ï¡¢
.sp
.in +4n
.nf
.BI "quad_t strtoq(const char *" nptr ", char **" endptr ", int " base );
.sp
.in
.fi
.\"O with completely analogous definition.
¤È¤¤¤¦´°Á´¤ËƱÍͤÎÄêµÁ¤ò»ý¤Ä´Ø¿ô¤¬¤¢¤ë¡£
.\"O Depending on the wordsize of the current architecture, this
.\"O may be equivalent to
.\"O .BR strtoll ()
.\"O or to
.\"O .BR strtol ().
»ÈÍÑÃæ¤Î¥¢¡¼¥­¥Æ¥¯¥Á¥ã¤Î¥ï¡¼¥ÉĹ¼¡Âè¤Ç¤¢¤ë¤¬¡¢¤³¤Î´Ø¿ô¤Ï
.BR strtoll ()
¤«
.BR strtol ()
¤ÈÅù²Á¤È¤Ê¤ë¤³¤È¤â¤¢¤ë¡£
.\"O .SH EXAMPLE
.SH Îã
.\"O The program shown below demonstrates the use of
.\"O .BR strtol ().
.\"O The first command-line argument specifies a string from which
.\"O .BR strtol ()
.\"O should parse a number.
.\"O The second (optional) argument specifies the base to be used for
.\"O the conversion.
.\"O (This argument is converted to numeric form using
.\"O .BR atoi (3),
.\"O a function that performs no error checking and
.\"O has a simpler interface than
.\"O .BR strtol ().)
°Ê²¼¤Î¥×¥í¥°¥é¥à¤Ï
.BR strtol ()
¤Î»ÈÍÑÎã¤Ç¤¢¤ë¡£
ºÇ½é¤Î¥³¥Þ¥ó¥É¥é¥¤¥ó°ú¤­¿ô¤Ë¤Ï
.BR strtol ()
¤¬¿ô»ú¤È¤·¤Æ²ò¼á¤¹¤ëʸ»úÎó¤ò»ØÄꤹ¤ë¡£
(¾Êά²Äǽ¤Ê) ÆóÈÖÌܤΰú¤­¿ô¤Ë¤Ï
ÊÑ´¹¤Ë»ÈÍѤµ¤ì¤ë´ð¿ô¤ò»ØÄꤹ¤ë
(¤³¤Î°ú¤­¿ô¤Ï
.BR atoi (3)
¤ò»È¤Ã¤Æ¿ôÃͤËÊÑ´¹¤µ¤ì¤ë¡£
.BR atoi (3)
¤Ï
.BR strtol ()
¤è¤ê¤â´Êñ¤Ê¥¤¥ó¥¿¥Õ¥§¡¼¥¹¤ò»ý¤Ä´Ø¿ô¤Ç¡¢
¤½¤ÎÃæ¤Ç¤Ï¥¨¥é¡¼¥Á¥§¥Ã¥¯¤Ï¹Ô¤ï¤ì¤Ê¤¤)¡£
.\"O Some examples of the results produced by this program are the following:
¤³¤Î¥×¥í¥°¥é¥à¤Î¼Â¹ÔÎã¤ò¤¤¤¯¤Ä¤«°Ê²¼¤Ë¼¨¤¹:
.in +4n
.nf

.RB "$" " ./a.out 123"
strtol() returned 123
.RB "$" " ./a.out \(aq    123\(aq"
strtol() returned 123
.RB "$" " ./a.out 123abc"
strtol() returned 123
Further characters after number: abc
.RB "$" " ./a.out 123abc 55"
strtol: Invalid argument
.RB "$" " ./a.out \(aq\(aq"
No digits were found
.RB "$" " ./a.out 4000000000"
strtol: Numerical result out of range
.fi
.in
.\"O .SS Program source
.SS ¥×¥í¥°¥é¥à¤Î¥½¡¼¥¹
\&
.nf
#include <stdlib.h>
#include <limits.h>
#include <stdio.h>
#include <errno.h>

int
main(int argc, char *argv[])
{
    int base;
    char *endptr, *str;
    long val;

    if (argc < 2) {
        fprintf(stderr, "Usage: %s str [base]\\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    str = argv[1];
    base = (argc > 2) ? atoi(argv[2]) : 10;

    errno = 0;    /* To distinguish success/failure after call */
    val = strtol(str, &endptr, base);

    /* Check for various possible errors */

    if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
            || (errno != 0 && val == 0)) {
        perror("strtol");
        exit(EXIT_FAILURE);
    }

    if (endptr == str) {
        fprintf(stderr, "No digits were found\\n");
        exit(EXIT_FAILURE);
    }

    /* If we got here, strtol() successfully parsed a number */

    printf("strtol() returned %ld\\n", val);

    if (*endptr != \(aq\\0\(aq)        /* Not necessarily an error... */
        printf("Further characters after number: %s\\n", endptr);

    exit(EXIT_SUCCESS);
}
.fi
.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR atof (3),
.BR atoi (3),
.BR atol (3),
.BR strtod (3),
.BR strtoul (3)