fread(3S)                                               fread(3S)



     NAME
          fread, fwrite - binary input/output

     SYNOPSIS
          #include <stdio.h>

          int fread (ptr, size, nitems, stream)
          char *ptr;
          int size, nitems;
          FILE *stream;

          int fwrite (ptr, size, nitems, stream)
          char *ptr;
          int size, nitems;
          FILE *stream;

     DESCRIPTION
          fread copies nitems items of data from the named input
          stream into an array beginning at ptr.  An item of data is a
          sequence of bytes (not necessarily terminated by a null
          byte) of length size.  fread stops appending bytes if an
          end-of-file or error condition is encountered while reading
          stream or if nitems items have been read.  fread leaves the
          file pointer in stream, if defined, pointing to the byte
          following the last byte read if there is one.  fread does
          not change the contents of stream.

          fwrite appends at most nitems items of data from the the
          array pointed to by ptr to the named output stream.  fwrite
          stops appending when it has appended nitems items of data or
          if an error condition is encountered on stream.  fwrite does
          not change the contents of the array pointed to by ptr.

          The variable size is typically sizeof(*ptr) where the
          pseudo-function sizeof specifies the length of an item
          pointed to by ptr.  If ptr points to a data type other than
          char it should be cast into a pointer to char.

     SEE ALSO
          read(2), write(3), fopen(3S), getc(3S), gets(3S),
          printf(3S), putc(3S), puts(3S), scanf(3S).

     DIAGNOSTICS
          fread and fwrite return the number of items read or written.
          If size or nitems is non-positive, no characters are read or
          written and 0 is returned by both fread and fwrite.









     Page 1                                        (last mod. 1/14/87)