PUTC(3S-SysV)       RISC/os Reference Manual        PUTC(3S-SysV)



NAME
     putc, putchar, fputc, putw - put 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
     putc writes the character c onto the output stream (at the
     position where the file pointer, if defined, is pointing).
     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 invocation and its name can be passed as an argu-
     ment to a function.

     putw writes the word (i.e. integer) w to the output stream
     (at the position at which the file pointer, if defined, is
     pointing).  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.

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

DIAGNOSTICS
     On success, these functions (with the exception of putw)
     each return the value they have written.  [Putw returns fer-
     ror (stream)].  On failure, they return the constant EOF.
     This will occur if the file stream is not open for writing
     or if the output file cannot grow.  Because EOF is a valid
     integer, ferror(3S) should be used to detect putw errors.





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PUTC(3S-SysV)       RISC/os Reference Manual        PUTC(3S-SysV)



CAVEATS
     Because it is implemented as a macro, putc evaluates a
     stream argument more than once.  In particular, putc(c,
     *f++); doesn't work sensibly.  fputc should be used instead.
     Because of possible differences in word length and byte ord-
     ering, files written using putw are machine-dependent, and
     may not be read using getw on a different processor.
















































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