term% cat index.txt PUTC(3S) PUTC(3S)
NAME
putc, putchar, fputc, putw - put character or word on a stream
SYNOPSIS
#include <stdio.h>
int putc(c, stream)
char c;
FILE *stream;
putchar(c)
fputc(c, stream)
FILE *stream;
putw(w, stream)
FILE *stream;
DESCRIPTION
Putc appends the character c to the named output stream. It returns
the character written.
Putchar(c) is defined as putc(c, stdout).
Fputc behaves like putc, but is a genuine function rather than a macro.
It may be used to save on object text.
Putw appends word (i.e. int) w to the output stream. It returns the
word written. Putw neither assumes nor causes special alignment in the
file.
The standard stream stdout is normally buffered if and only if the out‐
put does not refer to a terminal; this default may be changed by set‐
buf(3). The standard stream stderr is by default unbuffered uncondi‐
tionally, but use of freopen (see fopen(3)) will cause it to become
buffered; setbuf, again, will set the state to whatever is desired.
When an output stream is unbuffered information appears on the destina‐
tion file or terminal as soon as written; when it is buffered many
characters are saved up and written as a block. Fflush (see fclose(3))
may be used to force the block out early.
SEE ALSO
fopen(3), fclose(3), getc(3), puts(3), printf(3), fread(3)
DIAGNOSTICS
These functions return the constant EOF upon error. Since this is a
good integer, ferror(3) should be used to detect putw errors.
BUGS
Because it is implemented as a macro, putc treats a stream argument
with side effects improperly. In particular ‘putc(c, *f++);' doesn't
work sensibly.
PUTC(3S)