| FGETWLN(3) | Library Functions Manual | FGETWLN(3) |
fgetwln, fgetwln_l
— get a line of wide characters from a
stream
Standard C Library (libc, -lc)
#include <stdio.h>
#include <wchar.h>
wchar_t *
fgetwln(FILE
* restrict stream, size_t
* restrict len);
#include
<xlocale.h>
wchar_t *
fgetwln_l(FILE
* restrict stream, size_t
* restrict len, locale_t
loc);
The
fgetwln()
function returns a pointer to the next line from the stream referenced by
stream. This line is
not a
standard wide character string as it does not end with a terminating null
wide character. The length of the line, including the final newline, is
stored in the memory location to which len points.
(Note, however, that if the line is the last in a file that does not end in
a newline, the returned text will not contain a newline.)
While the
fgetwln()
function uses the current locale, the
fgetwln_l()
function may be passed a locale directly. See
xlocale(3) for more information.
Upon successful completion a pointer is returned; this pointer
becomes invalid after the next I/O operation on stream
(whether successful or not) or as soon as the stream is closed. Otherwise,
NULL is returned. The
fgetwln() function does not distinguish between
end-of-file and error; the routines
feof(3) and
ferror(3) must be used to determine
which occurred. If an error occurs, the global variable
errno is set to indicate the error. The end-of-file
condition is remembered, even on a terminal, and all subsequent attempts to
read will return NULL until the condition is cleared
with clearerr(3).
The text to which the returned pointer points may be modified, provided that no changes are made beyond the returned size. These changes are lost as soon as the pointer becomes invalid.
EBADF]The fgetwln() function may also fail and
set errno for any of the errors specified for the
routines mbrtowc(3),
realloc(3), or
read(2).
| July 16, 2004 | macOS 15.2 |