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toupper(3p) — Linux manual page

TOUPPER(3P)             POSIX Programmer's ManualTOUPPER(3P)

PROLOG        top

       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.

NAME        top

       toupper, toupper_l — transliterate lowercase characters to       uppercase

SYNOPSIS        top

       #include <ctype.h>       int toupper(intc);       int toupper_l(intc, locale_tlocale);

DESCRIPTION        top

       Fortoupper(): 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.       Thetoupper() andtoupper_l() functions have as a domain a typeint, the value of which is representable as anunsigned charor       the value of EOF. If the argument has any other value, the       behavior is undefined.       If the argument oftoupper() ortoupper_l() represents a lowercase       letter, and there exists a corresponding uppercase letter as       defined by character type information in the current locale or in       the locale represented bylocale, respectively (categoryLC_CTYPE), the result shall be the corresponding uppercase letter.       All other arguments in the domain are returned unchanged.       The behavior is undefined if thelocale argument totoupper_l() is       the special locale object LC_GLOBAL_LOCALE or is not a valid       locale object handle.

RETURN VALUE        top

       Upon successful completion,toupper() andtoupper_l() shall return       the uppercase letter corresponding to the argument passed;       otherwise, they shall return the argument unchanged.

ERRORS        top

       No errors are defined.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

setlocale(3p),uselocale(3p)       The Base Definitions volume of POSIX.1‐2017,Chapter 7,Locale,ctype.h(0p),locale.h(0p)

COPYRIGHT        top

       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                2017TOUPPER(3P)

Pages that refer to this page:ctype.h(0p), sort(1p), setlocale(3p), _toupper(3p)

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