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;
int putchar(c)
char c;
int fputc(c, stream)
char c;
FILE *stream;
int putw(w, stream)
int w;
FILE *stream;
DESCRIPTION
putc() writes the character c onto the standard I/O output stream
stream (at the position where the file pointer, if defined, is point-
ing). It returns the character written.
putchar(c) is defined as putc(c, stdout). putc() and putchar() are
macros.
fputc() behaves like putc(), but is a function rather than a macro.
fputc() runs more slowly than putc(), but it takes less space per invo-
cation and its name can be passed as an argument to a function.
putw() writes the C int (word) w to the standard I/O output stream
stream (at the position of the file pointer, if defined). The size of
a word is the size of an integer and varies from machine to machine.
putw() neither assumes nor causes special alignment in the file.
Output streams are by default buffered if the output refers to a file
and line-buffered if the output refers to a terminal. When an output
stream is unbuffered, information is queued for writing on the destina-
tionV),
setbuffer(), or setvbuf() may be used to change the stream's buffering
strategy.
SEE ALSO
fclose(3V), ferror(3V), fopen(3V), fread(3S), getc(3V), printf(3V),
puts(3S), setbuf(3V),
DIAGNOSTICS
On success, putc(), fputc(), and putchar() return the value that was
written. On error, those functions return the constant EOF. putw()
returns ferror(stream), so that it returns 0 on success and 1 on fail-
ure.
BUGS
Because it is implemented as a macro, putc() treats a stream argument
with side effects improperly. In particular, putc(c, *f++); does not
work sensibly. fputc() should be used instead.
Errors can occur long after the call to putc().
Because of possible differences in word length and byte ordering, files
written using putw() are machine-dependent, and may not be read using
getw() on a different processor.
10 October 1987 PUTC(3S)