< c‎ | string‎ | wide
Defined in header <wctype.h>
wint_t towlower( wint_t wc );
(since C95)

Converts the given wide character to lowercase, if possible.


[edit] Parameters

wc - wide character to be converted

[edit] Return value

Lowercase version of wc or unmodified wc if no lowercase version is listed in the current C locale.

[edit] Notes

Only 1:1 character mapping can be performed by this function, e.g. the Greek uppercase letter 'Σ' has two lowercase forms, depending on the position in a word: 'σ' and 'ς'. A call to towlower cannot be used to obtain the correct lowercase form in this case.

[edit] Example

#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
#include <locale.h>
int main(void)
    wchar_t wc = L'\u0190'; // Latin capital open E ('Ɛ')
    printf("in the default locale, towlower(%#x) = %#x\n", wc, towlower(wc));
    setlocale(LC_ALL, "en_US.utf8");
    printf("in Unicode locale, towlower(%#x) = %#x\n", wc, towlower(wc));


in the default locale, towlower(0x190) = 0x190
in Unicode locale, towlower(0x190) = 0x25b

[edit] References

  • C11 standard (ISO/IEC 9899:2011):
  • The towlower function (p: 453)
  • C99 standard (ISO/IEC 9899:1999):
  • The towlower function (p: 399)

[edit] See also

converts a wide character to uppercase
converts a character to lowercase
C++ documentation for towlower