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PROLOG |NAME |SYNOPSIS |DESCRIPTION |RETURN VALUE |ERRORS |EXAMPLES |APPLICATION USAGE |RATIONALE |FUTURE DIRECTIONS |SEE ALSO |COPYRIGHT | |
TOWCTRANS(3P) POSIX Programmer's ManualTOWCTRANS(3P)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.
towctrans, towctrans_l — wide-character transliteration
#include <wctype.h> wint_t towctrans(wint_twc, wctrans_tdesc); wint_t towctrans_l(wint_twc, wctrans_tdesc, locale_tlocale);
Fortowctrans(): The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2017 defers to the ISO C standard. Thetowctrans() andtowctrans_l() functions shall transliterate the wide-character codewc using the mapping described bydesc. The current setting of theLC_CTYPE category in the current locale or in the locale represented bylocale, respectively, should be the same as during the call towctrans() orwctrans_l() that returned the valuedesc. If the value ofdesc is invalid (that is, not obtained by a call towctrans() ordesc is invalidated by a subsequent call tosetlocale() that has affected categoryLC_CTYPE), the result is unspecified. If the value ofdesc is invalid (that is, not obtained by a call towctrans_l() with the same locale objectlocale) the result is unspecified. An application wishing to check for error situations should seterrno to 0 before callingtowctrans() ortowctrans_l(). Iferrno is non-zero on return, an error has occurred. The behavior is undefined if thelocale argument totowctrans_l() is the special locale object LC_GLOBAL_LOCALE or is not a valid locale object handle.
If successful, thetowctrans() andtowctrans_l() functions shall return the mapped value ofwc using the mapping described bydesc. Otherwise, they shall returnwc unchanged.
These functions may fail if:EINVALdesc contains an invalid transliteration descriptor.The following sections are informative.
None.
The strings"tolower"and"toupper"are reserved for the standard mapping names. In the table below, the functions in the left column are equivalent to the functions in the right column. towlower(wc) towctrans(wc, wctrans("tolower")) towlower_l(wc,locale) towctrans_l(wc, wctrans("tolower"),locale) towupper(wc) towctrans(wc, wctrans("toupper")) towupper_l(wc,locale) towctrans_l(wc, wctrans("toupper"),locale)None.
None.
towlower(3p),towupper(3p),wctrans(3p) The Base Definitions volume of POSIX.1‐2017,wctype.h(0p)
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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 athttp://www.opengroup.org/unix/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, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group 2017TOWCTRANS(3P)Pages that refer to this page:wctype.h(0p), wctrans(3p)
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