Copy a file, byte for byte

Introduction#

If you’re using SAS to produce reporting of some sort, you’re going to find yourself needing to copy a file at some point. I’ve mostly used this method for copying an excel template, and then dumping data via PROC EXPORT into the new file I’ve created.

This is a great example I’ve found from Chris Hemedinger (https://blogs.sas.com/content/sasdummy/2011/06/17/how-to-use-sas-data-step-to-copy-a-file-from-anywhere/).

Copying any file, byte by byte

/* these IN and OUT filerefs can point to anything */
filename in "anyfilehere.xlsx"; 
filename out "anyfilehere.xlsx"; 


/* copy the file byte-for-byte  */
data _null_;
  length filein 8 fileid 8;
  filein = fopen('in','I',1,'B');
  fileid = fopen('out','O',1,'B');
  rec = '20'x;
  do while(fread(filein)=0);
     rc = fget(filein,rec,1);
     rc = fput(fileid, rec);

     rc =fwrite(fileid);
  end;
  rc = fclose(filein);
  rc = fclose(fileid);
run;
 
filename in clear;
filename out clear;