This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
The uselocale() function shall set the current locale for the current
thread to the locale represented by newloc.
The value for the newloc argument shall be one of the following:
1. A value returned by the newlocale() or duplocale() functions
2. The special locale object descriptor LC_GLOBAL_LOCALE
Once the uselocale() function has been called to install a thread-
local locale, the behavior of every interface using data from the
current locale shall be affected for the calling thread. The current
locale for other threads shall remain unchanged.
If the newloc argument is (locale_t)0, the object returned is the
current locale or LC_GLOBAL_LOCALE if there has been no previous call
to uselocale() for the current thread.
If the newloc argument is LC_GLOBAL_LOCALE, the thread shall use the
global locale determined by the setlocale() function.
Upon successful completion, the uselocale() function shall return the
locale handle from the previous call for the current thread, or
LC_GLOBAL_LOCALE if there was no such previous call. Otherwise,
uselocale() shall return (locale_t)0 and set errno to indicate the
Unlike the setlocale() function, the uselocale() function does not
allow replacing some locale categories only. Applications that need
to install a locale which differs only in a few categories must use
newlocale() to change a locale object equivalent to the currently
used locale and install it.
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
IEEE/The Open Group 2013 USELOCALE(3P)