FREAD(3S)            INTERACTIVE UNIX System            FREAD(3S)



          NAME
               fread, fwrite - binary input/output

          SYNOPSIS
               #include <stdio.h>
               #include <sys/types.h>

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

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

          DESCRIPTION
               The fread function copies, into an array pointed to by ptr,
               nitems items of data from the named input stream, where an
               item of data is a sequence of bytes (not necessarily ter-
               minated by a null byte) of length size.  fread stops append-
               ing bytes if an end-of-file or error condition is encoun-
               tered 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 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 argument 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(2), fopen(3S), getc(3S), gets(3S),
               printf(3S), putc(3S), puts(3S), scanf(3S), stdio(3S).

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





          Rev. C Software Development Set                            Page 1