Date:         Tue, 31 Jan 2006 09:52:47 -0500
Reply-To:     "Richard A. DeVenezia" <rdevenezia@WILDBLUE.NET>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Richard A. DeVenezia" <rdevenezia@WILDBLUE.NET>
Subject:      Re: Random access with FOPEN(), FREAD(), FPOS() and FGET()
Comments: To: sas-l@uga.edu

Friar Broccoli wrote:
> Hi Mr DeVenezia;
>
> Thank you for taking the time to provide this alterate method for
> reading offset
> directed file structures.  Unfortunately I already knew of this method
> for solving this
> problem.  I presented my code as an example of a problem that could be
> solved
> with FGet etc.

Variety is a spice unto itself... but some spices are decidedly untasteful.

Note how the record-length and record-type are specified in the FOPEN to
allow you to read past the end of file.
-----------------------------
filename FOO "%sysfunc(pathname(WORK))/foo.txt";

data _null_;
  file FOO recfm=N;
  do i = 1 to 26;
    S = repeat (byte(64+i),6);
    put S $CHAR7. @;
  end;
run;

data _null_;
  length buffer $40;

  fid = fopen ('FOO','I',40,'B');
  put fid=;

  do until (rcread ne 0);
    rcread = fread (fid);
    rcget = fget(fid,buffer,40);
    put rcread= rcget= buffer=;
  end;

  fid = fclose(fid);
  put fid=;
run;
-----------------------------

Have fun maintaining your tangled skein.

Richard A. DeVenezia
http://www.devenezia.com/