PUTC(3) Library Functions Manual PUTC(3)
fputc, putc, putchar, putc_unlocked, putchar_unlocked, putw -- output a
character or word to a stream
Standard C Library (libc, -lc)
fputc(int c, FILE *stream);
putc(int c, FILE *stream);
putc_unlocked(int c, FILE *stream);
putw(int w, FILE *stream);
The fputc() function writes the character c (converted to an ``unsigned
char'') to the output stream pointed to by stream.
putc() acts essentially identically to fputc(), but is a macro that
expands in-line. It may evaluate stream more than once, so arguments
given to putc() should not be expressions with potential side effects.
putchar() is identical to putc() with an output stream of stdout.
The putc_unlocked() and putchar_unlocked() functions provide
functionality identical to that of putc() and putchar(), respectively,
but do not perform implicit locking of the streams they operate on. In
multi-threaded programs they may be used only within a scope in which the
stream has been successfully locked by the calling thread using either
flockfile(3) or ftrylockfile(3), and may later be released using
The putw() function writes the specified int to the named output stream.
The functions, fputc(), putc() and putchar() return the character
written. If an error occurs, the value EOF is returned. The putw()
function returns 0 on success; EOF is returned if a write error occurs,
or if an attempt is made to write a read-only stream.
ferror(3), fopen(3), getc(3), stdio(3)
The functions fputc(), putc(), and putchar(), conform to ANSI X3.159-1989
(``ANSI C89''). The functions putc_unlocked() and putchar_unlocked()
conform to ISO/IEC 9945-1:1996 (``POSIX.1'').
The functions putc(), putchar(), and putw() first appeared in Version 6
AT&T UNIX. The function fputc() appeared in Version 7 AT&T UNIX.
The size and byte order of an int varies from one machine to another, and
putw() is not recommended for portable applications.
NetBSD 6.1.5 May 6, 2010 NetBSD 6.1.5