_TOLOWER(3)                POSIX Programmer's Manual               _TOLOWER(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       _tolower -- transliterate uppercase characters to lowercase

SSYYNNOOPPSSIISS
       #include <ctype.h>

       int _tolower(int _c);

DDEESSCCRRIIPPTTIIOONN
       The ___t_o_l_o_w_e_r() macro shall be equivalent to _t_o_l_o_w_e_r(_c) except that the
       application shall ensure that the argument _c is an uppercase letter.

RREETTUURRNN VVAALLUUEE
       Upon successful completion, ___t_o_l_o_w_e_r() shall return the lowercase
       letter corresponding to the argument passed.

EERRRROORRSS
       No errors are defined.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       Applications should use the _t_o_l_o_w_e_r() function instead of the
       obsolescent ___t_o_l_o_w_e_r() function.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       The ___t_o_l_o_w_e_r() function may be removed in a future version.

SSEEEE AALLSSOO
       _t_o_l_o_w_e_r(), _i_s_u_p_p_e_r()

       The Base Definitions volume of POSIX.1-2017, _C_h_a_p_t_e_r _7, _L_o_c_a_l_e,
       <<ccttyyppee..hh>>

CCOOPPYYRRIIGGHHTT
       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 at http://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, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                          _TOLOWER(3)
