GETC(3S-SVR3)       RISC/os Reference Manual        GETC(3S-SVR3)



NAME
     getc, getchar, fgetc, getw - get character or word from a
          stream

SYNOPSIS
     #include <stdio.h>

     int getc (stream)
     FILE *stream;

     int getchar ()

     int fgetc (stream)
     FILE *stream;

     int getw (stream)
     FILE *stream;

DESCRIPTION
     getc returns the next character (i.e., byte) from the named
     input stream, as an integer.  It also moves the file
     pointer, if defined, ahead one character in stream.  getchar
     is defined as getc(stdin).  getc and getchararemacros.

     fgetc behaves like getc, but is a function rather than a
     macro.  fgetc runs more slowly than getc, but it takes less
     space per invocation and its name can be passed as an argu-
     ment to a function.

     getw returns the next word (i.e., integer) from the named
     input stream.  getw increments the associated file pointer,
     if defined, to point to the next word.  The size of a word
     is the size of an integer and varies from machine to
     machine.  getw assumes no special alignment in the file.

SEE ALSO
     fclose(3S), ferror(3S), fopen(3S), fread(3S), gets(3S),
     putc(3S), scanf(3S), stdio(3S).

DIAGNOSTICS
     These functions return the constant EOF at end-of-file or
     upon an error.  Because EOF is a valid integer, ferror(3S)
     should be used to detect getw errors.

WARNING
     If the integer value returned by getc, getchar, or fgetc is
     stored into a character variable and then compared against
     the integer constant EOF, the comparison may never succeed,
     because sign-extension of a character on widening to integer
     is machine-dependent.





                        Printed 11/19/92                   Page 1

GETC(3S-SVR3)       RISC/os Reference Manual        GETC(3S-SVR3)



CAVEATS
     Because it is implemented as a macro, getc evaluates a
     stream argument more than once.  In particular, getc(*f++)
     does not work sensibly.  fgetc 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.















































 Page 2                 Printed 11/19/92