wctob - cppreference.com (original) (raw)
| | | | | ----------------------- | | ----------- | | int wctob( wint_t c ); | | (since C95) |
Narrows a wide character c if its multibyte character equivalent in the initial shift state is a single byte.
This is typically possible for the characters from the ASCII character set, since most multibyte encodings (such as UTF-8) use single bytes to encode those characters.
[edit] Parameters
| c | - | wide character to narrow |
|---|
[edit] Return value
EOF if c does not represent a multibyte character with length 1 in initial shift state.
otherwise, the single-byte representation of c as unsigned char converted to int
[edit] Example
#include <locale.h> #include <wchar.h> #include <stdio.h> #include <assert.h> void try_narrowing(wchar_t c) { int cn = wctob(c); if(cn != EOF) printf("%#x narrowed to %#x\n", c, cn); else printf("%#x could not be narrowed\n", c); } int main(void) { char* utf_locale_present = setlocale(LC_ALL, "th_TH.utf8"); assert(utf_locale_present); puts("In Thai UTF-8 locale:"); try_narrowing(L'a'); try_narrowing(L'๛'); char* tis_locale_present = setlocale(LC_ALL, "th_TH.tis620"); assert(tis_locale_present); puts("In Thai TIS-620 locale:"); try_narrowing(L'a'); try_narrowing(L'๛'); }
Possible output:
In Thai UTF-8 locale: 0x61 narrowed to 0x61 0xe5b could not be narrowed In Thai TIS-620 locale: 0x61 narrowed to 0x61 0xe5b narrowed to 0xfb
[edit] References
C11 standard (ISO/IEC 9899:2011):
7.29.6.1.2 The wctob function (p: 441)
C99 standard (ISO/IEC 9899:1999):
7.24.6.1.2 The wctob function (p: 387)