fputwc, putwc, putwchar - put wide-character code on a
wint_t fputwc(wchar_t wc, FILE*stream);
wint_t putwc(wchar_t wc, FILE*stream);
wint_t putwchar(wchar_t wc);
The fputwc() function writes the character corresponding to
the wide-character code wc to the output stream pointed to
by stream, at the position indicated by the associated
file-position indicator for the stream (if defined), and
advances the indicator appropriately. If the file cannot
support positioning requests, or if the stream was opened
with append mode, the character is appended to the output
stream. If an error occurs while writing the character, the
shift state of the output file is left in an undefined
The st_ctime and st_mtime fields of the file will be marked
for update between the successful execution of fputwc() and
the next successful completion of a call to fflush(3C) or
fclose(3C) on the same stream or a call to exit(2) or
The putwc() function is equivalent to fputwc(), except that
it is implemented as a macro.
The call putwchar(wc) is equivalent to putwc(wc, stdout).
The putwchar() routine is implemented as a macro.
Upon successful completion, fputwc(), putwc(), and
putwchar() return wc. Otherwise, they return WEOF, the error
indicator for the stream is set, and errno is set to indi-
cate the error.
The fputwc(), putwc(), and putwchar() functions will fail if
either the stream is unbuffered or data in the stream's
buffer needs to be written, and:
The O_NONBLOCK flag is set for the file descriptor
underlying stream and the process would be delayed in
the write operation.
EBADF The file descriptor underlying stream is not a valid
file descriptor open for writing.
EFBIG An attempt was made to write to a file that exceeds
the maximum file size or the process's file size
limit; or the file is a regular file and an attempt
was made to write at or beyond the offset maximum
associated with the corresponding stream.
EINTR The write operation was terminated due to the receipt
of a signal, and no data was transferred.
EIO A physical I/O error has occurred, or the process is a
member of a background process group attempting to
write to its controlling terminal, TOSTOP is set, the
process is neither ignoring nor blocking SIGTTOU, and
the process group of the process is orphaned.
There was no free space remaining on the device con-
taining the file.
EPIPE An attempt is made to write to a pipe or FIFO that is
not open for reading by any process. A SIGPIPE signal
will also be sent to the process.
The fputwc(), putwc(), and putwchar() functions may fail if:
Insufficient storage space is available.
ENXIO A request was made of a non-existent device, or the
request was outside the capabilities of the device.
The wide-character code wc does not correspond to a
Functions exist for the putwc() and putwchar() macros. To
get the function form, the macro name must be undefined (for
example, #undef putc).
When the macro form is used, putwc() evaluates the stream
argument more than once. In particular, putwc(wc, *f++) does
not work sensibly. The fputwc() function should be used
instead when evaluating the stream argument has side
When a UFS file system is mounted with logging enabled, file
system transactions that free blocks from files might not
actually add those freed blocks to the file system's free
list until some unspecified time in the future. This
behavior improves file system performance but does not con-
form to the POSIX, Single UNIX Specification, SPARC Confor-
mance Definition, System V Application Binary Interface,
System V Interface Definition, and X/Open Portability Guide
Standards, which require that freed space be available
immediately. To enable standards conformance regarding file
deletions or to address the problem of not being able to
grow files on a relatively full UFS file system even after
files have been deleted, disable UFS logging (see
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| MT-Level | MT-Safe |
mount_ufs(1M), exit(2), ulimit(2), abort(3C), fclose(3C),
ferror(3C), fflush(3C), fopen(3C), setbuf(3C), attributes(5)
Man(1) output converted with