NAME

wcswidth — number of column positions of a wide-character string

SYNOPSIS

[XSI] #include <wchar.h>

int wcswidth(const wchar_t *pwcs, size_t n);

DESCRIPTION

The wcswidth() function shall determine the number of column positions required for n wide-character codes (or fewer than n wide-character codes if a null wide-character code is encountered before n wide-character codes are exhausted) in the string pointed to by pwcs.

The wcswidth() function shall not change the setting of errno on valid input.

RETURN VALUE

The wcswidth() function either shall return 0 (if pwcs points to a null wide-character code), or return the number of column positions to be occupied by the wide-character string pointed to by pwcs, or return -1 (if any of the first n wide-character codes in the wide-character string pointed to by pwcs is not a printable wide-character code).

ERRORS

No errors are defined.

EXAMPLES

None.

APPLICATION USAGE

This function was removed from the final ISO/IEC 9899:1990/Amendment 1:1995 (E), and the return value for a non-printable wide character is not specified.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

wcwidth

XBD 3.75 Column Position, <wchar.h>

CHANGE HISTORY

First released in Issue 4. Derived from the MSE working draft.

Issue 6

The Open Group Corrigendum U021/11 is applied. The function is marked as an extension.

Issue 8

Austin Group Defect 448 is applied, adding a requirement that wcswidth() does not change the setting of errno on valid input.