putc(3S)                                                 putc(3S)



NAME
     putc, putchar, fputc, putw - put a character or  word  on  a
     stream

SYNOPSIS
     #include <stdio.h>

     int putc(c, stream)
     int c;
     FILE *stream;

     int putchar(c)
     int c;

     int fputc(c, stream)
     int c;
     FILE *stream;

     int putw(w, stream)
     int w;
     FILE *stream;

DESCRIPTION
     The putc macro writes the character c onto the output stream
     at the position where the file pointer, if defined, is
     pointing.  The putchar macro is defined as putc(c, stdout).

     fputc behaves like putc, but is a function rather than a
     macro.  fputc runs more slowly than putc, but it takes less
     space per invocation and its name can be passed as an
     argument to a function.

     putw writes the word (32-bit integer on the Macintosh II) w
     to the output stream at the position at which the file
     pointer, if defined, is pointing.  putw neither assumes nor
     causes special alignment in the file.

     Output streams, with the exception of the standard error
     stream stderr, are by default buffered if the output refers
     to a file and line-buffered if the output refers to a
     terminal.  The standard error output stream stderr is by
     default unbuffered, but use of freopen (see fopen(3S))
     causes it to become buffered or line-buffered.  When an
     output stream is unbuffered information, it is queued for
     writing on the destination file or terminal as soon as
     written; when it is buffered, many characters are saved up
     and written as a block; when it is line-buffered, each line
     of output is queued for writing on the destination terminal
     as soon as the line is completed (i.e., as soon as a newline
     character is written or terminal input is requested).
     setbuf(3S) may be used to change the stream's buffering
     strategy.



January 1992                                                    1

putc(3S)                                                 putc(3S)



STATUS MESSAGES AND VALUES
     On success, these functions each return the value they have
     written.  On failure, they return the constant EOF.  This
     occurs if the file stream is not open for writing or if the
     output file cannot be grown.  Because EOF is a valid
     integer, ferror(3S) should be used to detect putw errors.

LIMITATIONS
     Because it is implemented as a macro, putc treats
     incorrectly a stream argument with side effects.  In
     particular, putc(c, *f++); doesn't work sensibly.  fputc
     should be used instead.

     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.

SEE ALSO
     fclose(3S), ferror(3S), fopen(3S), fread(3S), getc(3S),
     printf(3S), puts(3S), setbuf(3S)



































2                                                    January 1992