topic Re: timing issues with filename function and infile statement? in SAS Programming

timing issues with filename function and infile statement?

js5 — Wed, 10 Aug 2022 12:13:50 GMT

Hello,

I am having issues getting the filename function and infile statement to work nicely within one data step. The following code results in an error:

ERROR: No logical assign for filename PWFILE.

rc = filename("pwfile", catx("\", pathname("path"), "Password.txt"));
infile pwfile;
input password;
rc = filename("pwfile");

It is as if there is a timing issue with the fileref not being defined when infile wants to use it. I was able to work it around as follows:

password_file = catx("\", pathname("path"), "Password.txt");
infile dummy filevar=password_file;
input password;

It feels strange to use filevar to read only one file though. Is this behaviour expected? I cannot use filename statement beforehand because the code looks through the folder tree and only defines the fileref when it finds the latest folder. Thank you.

Re: timing issues with filename function and infile statement?

WarrenKuhfeld — Wed, 10 Aug 2022 12:43:27 GMT

Look at FILEVAR=.

https://v8doc.sas.com/sashtml/lgref/z0146932.htm#z0166950

I know this is an old link, but it is the one I could easily find.

Re: timing issues with filename function and infile statement?

mkeintz — Wed, 10 Aug 2022 12:48:16 GMT

@js5 :

You are essentially correct.

The "rc=filename(....)" statement is an executable statement - i.e. it won't be honored until the data step begins data processing. After all, like all functions, it could be a result of an "IF ... THEN rc=filename(...)" statement, which means it can only be executed during actual data processin.

But the INFILE statement in your initial code is effectively a compile-time statement that must be established prior to execution.

Using the "filevar=" option tells SAS that it must be prepared to dynamically assign a physical file to a fileref (even if it is just a single unchanging assignment).