1USELOCALE(3P) POSIX Programmer's Manual USELOCALE(3P)
2
3
4
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 uselocale — use locale in current thread
13
15 #include <locale.h>
16
17 locale_t uselocale(locale_t newloc);
18
20 The uselocale() function shall set or query the current locale for the
21 calling thread.
22
23 The value for the newloc argument shall be one of the following:
24
25 1. A value returned by the newlocale() or duplocale() functions
26
27 2. The special locale object descriptor LC_GLOBAL_LOCALE
28
29 3. (locale_t)0
30
31 If the newloc argument is (locale_t)0, the current locale shall not be
32 changed; this value can be used to query the current locale setting. If
33 the newloc argument is LC_GLOBAL_LOCALE, any thread-local locale for
34 the calling thread shall be uninstalled; the thread shall again use the
35 global locale as the current locale, and changes to the global locale
36 shall affect the thread. Otherwise, the locale represented by newloc
37 shall be installed as a thread-local locale to be used as the current
38 locale for the calling thread.
39
40 Once the uselocale() function has been called to install a thread-local
41 locale, the behavior of every interface using data from the current
42 locale shall be affected for the calling thread. The current locale for
43 other threads shall remain unchanged.
44
46 Upon successful completion, the uselocale() function shall return a
47 handle for the thread-local locale that was in use as the current
48 locale for the calling thread on entry to the function, or
49 LC_GLOBAL_LOCALE if no thread-local locale was in use. Otherwise, use‐
50 locale() shall return (locale_t)0 and set errno to indicate the error.
51
53 The uselocale() function may fail if:
54
55 EINVAL newloc is not a valid locale object and is not (locale_t)0.
56
57 The following sections are informative.
58
60 None.
61
63 Unlike the setlocale() function, the uselocale() function does not
64 allow replacing some locale categories only. Applications that need to
65 install a locale which differs only in a few categories must use newlo‐
66 cale() to change a locale object equivalent to the currently used
67 locale and install it.
68
70 None.
71
73 None.
74
76 duplocale(), freelocale(), newlocale(), setlocale()
77
78 The Base Definitions volume of POSIX.1‐2017, <locale.h>
79
81 Portions of this text are reprinted and reproduced in electronic form
82 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
83 table Operating System Interface (POSIX), The Open Group Base Specifi‐
84 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
85 Electrical and Electronics Engineers, Inc and The Open Group. In the
86 event of any discrepancy between this version and the original IEEE and
87 The Open Group Standard, the original IEEE and The Open Group Standard
88 is the referee document. The original Standard can be obtained online
89 at http://www.opengroup.org/unix/online.html .
90
91 Any typographical or formatting errors that appear in this page are
92 most likely to have been introduced during the conversion of the source
93 files to man page format. To report such errors, see https://www.ker‐
94 nel.org/doc/man-pages/reporting_bugs.html .
95
96
97
98IEEE/The Open Group 2017 USELOCALE(3P)