diff options
Diffstat (limited to 'man/man3/newlocale.3')
| -rw-r--r-- | man/man3/newlocale.3 | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/man/man3/newlocale.3 b/man/man3/newlocale.3 new file mode 100644 index 000000000..e6b29f875 --- /dev/null +++ b/man/man3/newlocale.3 @@ -0,0 +1,356 @@ +.\" Copyright (C) 2014 Michael Kerrisk <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH newlocale 3 (date) "Linux man-pages (unreleased)" +.SH NAME +newlocale, freelocale \- create, modify, and free a locale object +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <locale.h> +.P +.BI "locale_t newlocale(int " category_mask ", const char *" locale , +.BI " locale_t " base ); +.BI "void freelocale(locale_t " locobj ); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR newlocale (), +.BR freelocale (): +.nf + Since glibc 2.10: + _XOPEN_SOURCE >= 700 + Before glibc 2.10: + _GNU_SOURCE +.fi +.SH DESCRIPTION +The +.BR newlocale () +function creates a new locale object, or modifies an existing object, +returning a reference to the new or modified object as the function result. +Whether the call creates a new object or modifies an existing object +is determined by the value of +.IR base : +.IP \[bu] 3 +If +.I base +is +.IR "(locale_t)\ 0" , +a new object is created. +.IP \[bu] +If +.I base +refers to valid existing locale object +(i.e., an object returned by a previous call to +.BR newlocale () +or +.BR duplocale (3)), +then that object is modified by the call. +If the call is successful, the contents of +.I base +are unspecified (in particular, the object referred to by +.I base +may be freed, and a new object created). +Therefore, the caller should ensure that it stops using +.I base +before the call to +.BR newlocale (), +and should subsequently refer to the modified object via the +reference returned as the function result. +If the call fails, the contents of +.I base +remain valid and unchanged. +.P +If +.I base +is the special locale object +.B LC_GLOBAL_LOCALE +(see +.BR duplocale (3)), +or is not +.I (locale_t)\ 0 +and is not a valid locale object handle, +the behavior is undefined. +.P +The +.I category_mask +argument is a bit mask that specifies the locale categories +that are to be set in a newly created locale object +or modified in an existing object. +The mask is constructed by a bitwise OR of the constants +.BR LC_ADDRESS_MASK , +.BR LC_CTYPE_MASK , +.BR LC_COLLATE_MASK , +.BR LC_IDENTIFICATION_MASK , +.BR LC_MEASUREMENT_MASK , +.BR LC_MESSAGES_MASK , +.BR LC_MONETARY_MASK , +.BR LC_NUMERIC_MASK , +.BR LC_NAME_MASK , +.BR LC_PAPER_MASK , +.BR LC_TELEPHONE_MASK , +and +.BR LC_TIME_MASK . +Alternatively, the mask can be specified as +.BR LC_ALL_MASK , +which is equivalent to ORing all of the preceding constants. +.P +For each category specified in +.IR category_mask , +the locale data from +.I locale +will be used in the object returned by +.BR newlocale (). +If a new locale object is being created, +data for all categories not specified in +.I category_mask +is taken from the default ("POSIX") locale. +.P +The following preset values of +.I locale +are defined for all categories that can be specified in +.IR category_mask : +.TP +"POSIX" +A minimal locale environment for C language programs. +.TP +"C" +Equivalent to "POSIX". +.TP +"" +An implementation-defined native environment +corresponding to the values of the +.B LC_* +and +.B LANG +environment variables (see +.BR locale (7)). +.SS freelocale() +The +.BR freelocale () +function deallocates the resources associated with +.IR locobj , +a locale object previously returned by a call to +.BR newlocale () +or +.BR duplocale (3). +If +.I locobj +is +.B LC_GLOBAL_LOCALE +or is not valid locale object handle, the results are undefined. +.P +Once a locale object has been freed, +the program should make no further use of it. +.SH RETURN VALUE +On success, +.BR newlocale () +returns a handle that can be used in calls to +.BR duplocale (3), +.BR freelocale (), +and other functions that take a +.I locale_t +argument. +On error, +.BR newlocale () +returns +.IR "(locale_t)\ 0", +and sets +.I errno +to indicate the error. +.SH ERRORS +.TP +.B EINVAL +One or more bits in +.I category_mask +do not correspond to a valid locale category. +.TP +.B EINVAL +.I locale +is NULL. +.TP +.B ENOENT +.I locale +is not a string pointer referring to a valid locale. +.TP +.B ENOMEM +Insufficient memory to create a locale object. +.SH STANDARDS +POSIX.1-2008. +.SH HISTORY +glibc 2.3. +.SH NOTES +Each locale object created by +.BR newlocale () +should be deallocated using +.BR freelocale (). +.SH EXAMPLES +The program below takes up to two command-line arguments, +which each identify locales. +The first argument is required, and is used to set the +.B LC_NUMERIC +category in a locale object created using +.BR newlocale (). +The second command-line argument is optional; +if it is present, it is used to set the +.B LC_TIME +category of the locale object. +.P +Having created and initialized the locale object, +the program then applies it using +.BR uselocale (3), +and then tests the effect of the locale changes by: +.IP (1) 5 +Displaying a floating-point number with a fractional part. +This output will be affected by the +.B LC_NUMERIC +setting. +In many European-language locales, +the fractional part of the number is separated from the integer part +using a comma, rather than a period. +.IP (2) +Displaying the date. +The format and language of the output will be affected by the +.B LC_TIME +setting. +.P +The following shell sessions show some example runs of this program. +.P +Set the +.B LC_NUMERIC +category to +.I fr_FR +(French): +.P +.in +4n +.EX +$ \fB./a.out fr_FR\fP +123456,789 +Fri Mar 7 00:25:08 2014 +.EE +.in +.P +Set the +.B LC_NUMERIC +category to +.I fr_FR +(French), +and the +.B LC_TIME +category to +.I it_IT +(Italian): +.P +.in +4n +.EX +$ \fB./a.out fr_FR it_IT\fP +123456,789 +ven 07 mar 2014 00:26:01 CET +.EE +.in +.P +Specify the +.B LC_TIME +setting as an empty string, +which causes the value to be taken from environment variable settings +(which, here, specify +.IR mi_NZ , +New Zealand Māori): +.P +.in +4n +.EX +$ LC_ALL=mi_NZ ./a.out fr_FR "" +123456,789 +Te Paraire, te 07 o Poutū\-te\-rangi, 2014 00:38:44 CET +.EE +.in +.SS Program source +.\" SRC BEGIN (newlocale.c) +.EX +#define _XOPEN_SOURCE 700 +#include <locale.h> +#include <stdio.h> +#include <stdlib.h> +#include <time.h> +\& +#define errExit(msg) do { perror(msg); exit(EXIT_FAILURE); \e + } while (0) +\& +int +main(int argc, char *argv[]) +{ + char buf[100]; + time_t t; + size_t s; + struct tm *tm; + locale_t loc, nloc; +\& + if (argc < 2) { + fprintf(stderr, "Usage: %s locale1 [locale2]\en", argv[0]); + exit(EXIT_FAILURE); + } +\& + /* Create a new locale object, taking the LC_NUMERIC settings + from the locale specified in argv[1]. */ +\& + loc = newlocale(LC_NUMERIC_MASK, argv[1], (locale_t) 0); + if (loc == (locale_t) 0) + errExit("newlocale"); +\& + /* If a second command\-line argument was specified, modify the + locale object to take the LC_TIME settings from the locale + specified in argv[2]. We assign the result of this newlocale() + call to \[aq]nloc\[aq] rather than \[aq]loc\[aq], since in some cases, we might + want to preserve \[aq]loc\[aq] if this call fails. */ +\& + if (argc > 2) { + nloc = newlocale(LC_TIME_MASK, argv[2], loc); + if (nloc == (locale_t) 0) + errExit("newlocale"); + loc = nloc; + } +\& + /* Apply the newly created locale to this thread. */ +\& + uselocale(loc); +\& + /* Test effect of LC_NUMERIC. */ +\& + printf("%8.3f\en", 123456.789); +\& + /* Test effect of LC_TIME. */ +\& + t = time(NULL); + tm = localtime(&t); + if (tm == NULL) + errExit("time"); +\& + s = strftime(buf, sizeof(buf), "%c", tm); + if (s == 0) + errExit("strftime"); +\& + printf("%s\en", buf); +\& + /* Free the locale object. */ +\& + uselocale(LC_GLOBAL_LOCALE); /* So \[aq]loc\[aq] is no longer in use */ + freelocale(loc); +\& + exit(EXIT_SUCCESS); +} +.EE +.\" SRC END +.SH SEE ALSO +.BR locale (1), +.BR duplocale (3), +.BR setlocale (3), +.BR uselocale (3), +.BR locale (5), +.BR locale (7) |