xref: /freebsd/lib/libc/locale/xlocale.3 (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
1.\" Copyright (c) 2011 The FreeBSD Foundation
2.\"
3.\" This documentation was written by David Chisnall under sponsorship from
4.\" the FreeBSD Foundation.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\"
15.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25.\" SUCH DAMAGE.
26.\"
27.Dd September 17, 2011
28.Dt XLOCALE 3
29.Os
30.Sh NAME
31.Nm xlocale
32.Nd Thread-safe extended locale support
33.Sh LIBRARY
34.Lb libc
35.Sh SYNOPSIS
36.In xlocale.h
37.Sh DESCRIPTION
38The extended locale support includes a set of functions for setting
39thread-local locales,
40as well convenience functions for performing locale-aware
41calls with a specified locale.
42.Pp
43The core of the xlocale API is the
44.Fa locale_t
45type.
46This is an opaque type encapsulating a locale.
47Instances of this can be either set as the locale for a specific thread or
48passed directly to the
49.Fa _l
50suffixed variants of various standard C functions.
51Two special
52.Fa locale_t
53values are available:
54.Bl -bullet -offset indent
55.It
56NULL refers to the current locale for the thread,
57or to the global locale if no locale has been set for this thread.
58.It
59LC_GLOBAL_LOCALE refers to the global locale.
60.El
61.Pp
62The global locale is the locale set with the
63.Xr setlocale 3
64function.
65.Sh SEE ALSO
66.Xr duplocale 3 ,
67.Xr freelocale 3 ,
68.Xr localeconv 3 ,
69.Xr newlocale 3 ,
70.Xr querylocale 3 ,
71.Xr uselocale 3
72.Sh CONVENIENCE FUNCTIONS
73The xlocale API includes a number of
74.Fa _l
75suffixed convenience functions.
76These are variants of standard C functions
77that have been modified to take an explicit
78.Fa locale_t
79parameter as the final argument or, in the case of variadic functions,
80as an additional argument directly before the format string.
81Each of these functions accepts either NULL or LC_GLOBAL_LOCALE.
82In these functions, NULL refers to the C locale,
83rather than the thread's current locale.
84If you wish to use the thread's current locale,
85then use the unsuffixed version of the function.
86.Pp
87These functions are exposed by including
88.In xlocale.h
89.Em after
90including the relevant headers for the standard variant.
91For example, the
92.Xr strtol_l 3
93function is exposed by including
94.In xlocale.h
95after
96.In stdlib.h ,
97which defines
98.Xr strtol 3 .
99.Pp
100For reference,
101a complete list of the locale-aware functions that are available in this form,
102along with the headers that expose them, is provided here:
103.Bl -tag -width "<monetary.h> "
104.It In wctype.h
105.Xr iswalnum_l 3 ,
106.Xr iswalpha_l 3 ,
107.Xr iswcntrl_l 3 ,
108.Xr iswctype_l 3 ,
109.Xr iswdigit_l 3 ,
110.Xr iswgraph_l 3 ,
111.Xr iswlower_l 3 ,
112.Xr iswprint_l 3 ,
113.Xr iswpunct_l 3 ,
114.Xr iswspace_l 3 ,
115.Xr iswupper_l 3 ,
116.Xr iswxdigit_l 3 ,
117.Xr towlower_l 3 ,
118.Xr towupper_l 3 ,
119.Xr wctype_l 3 ,
120.It In ctype.h
121.Xr digittoint_l 3 ,
122.Xr isalnum_l 3 ,
123.Xr isalpha_l 3 ,
124.Xr isblank_l 3 ,
125.Xr iscntrl_l 3 ,
126.Xr isdigit_l 3 ,
127.Xr isgraph_l 3 ,
128.Xr ishexnumber_l 3 ,
129.Xr isideogram_l 3 ,
130.Xr islower_l 3 ,
131.Xr isnumber_l 3 ,
132.Xr isphonogram_l 3 ,
133.Xr isprint_l 3 ,
134.Xr ispunct_l 3 ,
135.Xr isrune_l 3 ,
136.Xr isspace_l 3 ,
137.Xr isspecial_l 3 ,
138.Xr isupper_l 3 ,
139.Xr isxdigit_l 3 ,
140.Xr tolower_l 3 ,
141.Xr toupper_l 3
142.It In inttypes.h
143.Xr strtoimax_l 3 ,
144.Xr strtoumax_l 3 ,
145.Xr wcstoimax_l 3 ,
146.Xr wcstoumax_l 3
147.It In langinfo.h
148.Xr nl_langinfo_l 3
149.It In monetary.h
150.Xr strfmon_l 3
151.It In stdio.h
152.Xr asprintf_l 3 ,
153.Xr fprintf_l 3 ,
154.Xr fscanf_l 3 ,
155.Xr printf_l 3 ,
156.Xr scanf_l 3 ,
157.Xr snprintf_l 3 ,
158.Xr sprintf_l 3 ,
159.Xr sscanf_l 3 ,
160.Xr vasprintf_l 3 ,
161.Xr vfprintf_l 3 ,
162.Xr vfscanf_l 3 ,
163.Xr vprintf_l 3 ,
164.Xr vscanf_l 3 ,
165.Xr vsnprintf_l 3 ,
166.Xr vsprintf_l 3 ,
167.Xr vsscanf_l 3
168.It In stdlib.h
169.Xr atof_l 3 ,
170.Xr atoi_l 3 ,
171.Xr atol_l 3 ,
172.Xr atoll_l 3 ,
173.Xr mblen_l 3 ,
174.Xr mbstowcs_l 3 ,
175.Xr mbtowc_l 3 ,
176.Xr strtod_l 3 ,
177.Xr strtof_l 3 ,
178.Xr strtol_l 3 ,
179.Xr strtold_l 3 ,
180.Xr strtoll_l 3 ,
181.Xr strtoul_l 3 ,
182.Xr strtoull_l 3 ,
183.Xr wcstombs_l 3 ,
184.Xr wctomb_l 3
185.It In string.h
186.Xr strcoll_l 3 ,
187.Xr strxfrm_l 3 ,
188.Xr strcasecmp_l 3 ,
189.Xr strcasestr_l 3 ,
190.Xr strncasecmp_l 3
191.It In time.h
192.Xr strftime_l 3
193.Xr strptime_l 3
194.It In wchar.h
195.Xr btowc_l 3 ,
196.Xr fgetwc_l 3 ,
197.Xr fgetws_l 3 ,
198.Xr fputwc_l 3 ,
199.Xr fputws_l 3 ,
200.Xr fwprintf_l 3 ,
201.Xr fwscanf_l 3 ,
202.Xr getwc_l 3 ,
203.Xr getwchar_l 3 ,
204.Xr mbrlen_l 3 ,
205.Xr mbrtowc_l 3 ,
206.Xr mbsinit_l 3 ,
207.Xr mbsnrtowcs_l 3 ,
208.Xr mbsrtowcs_l 3 ,
209.Xr putwc_l 3 ,
210.Xr putwchar_l 3 ,
211.Xr swprintf_l 3 ,
212.Xr swscanf_l 3 ,
213.Xr ungetwc_l 3 ,
214.Xr vfwprintf_l 3 ,
215.Xr vfwscanf_l 3 ,
216.Xr vswprintf_l 3 ,
217.Xr vswscanf_l 3 ,
218.Xr vwprintf_l 3 ,
219.Xr vwscanf_l 3 ,
220.Xr wcrtomb_l 3 ,
221.Xr wcscoll_l 3 ,
222.Xr wcsftime_l 3 ,
223.Xr wcsnrtombs_l 3 ,
224.Xr wcsrtombs_l 3 ,
225.Xr wcstod_l 3 ,
226.Xr wcstof_l 3 ,
227.Xr wcstol_l 3 ,
228.Xr wcstold_l 3 ,
229.Xr wcstoll_l 3 ,
230.Xr wcstoul_l 3 ,
231.Xr wcstoull_l 3 ,
232.Xr wcswidth_l 3 ,
233.Xr wcsxfrm_l 3 ,
234.Xr wctob_l 3 ,
235.Xr wcwidth_l 3 ,
236.Xr wprintf_l 3 ,
237.Xr wscanf_l 3
238.It In wctype.h
239.Xr iswblank_l 3 ,
240.Xr iswhexnumber_l 3 ,
241.Xr iswideogram_l 3 ,
242.Xr iswnumber_l 3 ,
243.Xr iswphonogram_l 3 ,
244.Xr iswrune_l 3 ,
245.Xr iswspecial_l 3 ,
246.Xr nextwctype_l 3 ,
247.Xr towctrans_l 3 ,
248.Xr wctrans_l 3
249.It In xlocale.h
250.Xr localeconv_l 3
251.El
252.Sh STANDARDS
253The functions
254conform to
255.St -p1003.1-2008 .
256.Sh HISTORY
257The xlocale APIs first appeared in Darwin 8.0.
258This implementation was written by David Chisnall,
259under sponsorship from the FreeBSD Foundation and first appeared in
260.Fx 9.1 .
261.Sh CAVEATS
262The
263.Xr setlocale 3
264function, and others in the family, refer to the global locale.
265Other functions that depend on the locale, however,
266will take the thread-local locale if one has been set.
267This means that the idiom of setting the locale using
268.Xr setlocale 3 ,
269calling a locale-dependent function,
270and then restoring the locale will not
271have the expected behavior if the current thread has had a locale set using
272.Xr uselocale 3 .
273You should avoid this idiom and prefer to use the
274.Fa _l
275suffixed versions instead.
276