This section describes functions for performing character- and line-oriented output.
These narrow streams functions are declared in the header file stdio.h and the wide stream functions in wchar.h.
The
fputc
function converts the character c to typeunsigned char
, and writes it to the stream stream.EOF
is returned if a write error occurs; otherwise the character c is returned.
The
fputwc
function writes the wide character wc to the stream stream.WEOF
is returned if a write error occurs; otherwise the character wc is returned.
The
fputc_unlocked
function is equivalent to thefputc
function except that it does not implicitly lock the stream.
The
fputwc_unlocked
function is equivalent to thefputwc
function except that it does not implicitly lock the stream.This function is a GNU extension.
This is just like
fputc
, except that most systems implement it as a macro, making it faster. One consequence is that it may evaluate the stream argument more than once, which is an exception to the general rule for macros.putc
is usually the best function to use for writing a single character.
This is just like
fputwc
, except that it can be implement as a macro, making it faster. One consequence is that it may evaluate the stream argument more than once, which is an exception to the general rule for macros.putwc
is usually the best function to use for writing a single wide character.
The
putc_unlocked
function is equivalent to theputc
function except that it does not implicitly lock the stream.
The
putwc_unlocked
function is equivalent to theputwc
function except that it does not implicitly lock the stream.This function is a GNU extension.
The
putchar
function is equivalent toputc
withstdout
as the value of the stream argument.
The
putwchar
function is equivalent toputwc
withstdout
as the value of the stream argument.
The
putchar_unlocked
function is equivalent to theputchar
function except that it does not implicitly lock the stream.
The
putwchar_unlocked
function is equivalent to theputwchar
function except that it does not implicitly lock the stream.This function is a GNU extension.
The function
fputs
writes the string s to the stream stream. The terminating null character is not written. This function does not add a newline character, either. It outputs only the characters in the string.This function returns
EOF
if a write error occurs, and otherwise a non-negative value.For example:
fputs ("Are ", stdout); fputs ("you ", stdout); fputs ("hungry?\n", stdout);outputs the text ‘Are you hungry?’ followed by a newline.
The function
fputws
writes the wide character string ws to the stream stream. The terminating null character is not written. This function does not add a newline character, either. It outputs only the characters in the string.This function returns
WEOF
if a write error occurs, and otherwise a non-negative value.
The
fputs_unlocked
function is equivalent to thefputs
function except that it does not implicitly lock the stream.This function is a GNU extension.
The
fputws_unlocked
function is equivalent to thefputws
function except that it does not implicitly lock the stream.This function is a GNU extension.
The
puts
function writes the string s to the streamstdout
followed by a newline. The terminating null character of the string is not written. (Note thatfputs
does not write a newline as this function does.)
puts
is the most convenient function for printing simple messages. For example:puts ("This is a message.");outputs the text ‘This is a message.’ followed by a newline.
This function writes the word w (that is, an
int
) to stream. It is provided for compatibility with SVID, but we recommend you usefwrite
instead (see Block Input/Output).