topic How to conditionally assign a library on a unix server in SAS Enterprise Guide

How to conditionally assign a library on a unix server

alepage — Thu, 17 Apr 2025 19:48:44 GMT

I have tried this script and it is not working. It always want to declare the libname even if it already exits

%macro test;
*libname data clear;
data test;
keep response;
response =libref("data");
%if response ne 0 %then 
%do;
	%PUT "Creating the libname data";
	LIBNAME data "&path1./data/";
%end;
run;

%mend test;
%test;

How to solve that issue

Re: How to conditionally assign a library on a unix server

PaigeMiller — Thu, 17 Apr 2025 21:06:12 GMT

%IF cannot access values of a data step variable such as response.

Maybe like this:

/* UNTESTED CODE */

%let response = %sysfunc(libref(data));
%put &=response;

%if &response ne 0 %then %do;
    %PUT Creating the libname data;
    options dlcreatedir;
    LIBNAME data "&path1/data";
%end;

Which brings up the question ... why bother testing? If DATA is a currently assigned libname, or if it NOT a currently assigned libname, the LIBNAME statement should execute without problems. No conditional branching is needed here.

Is this related to your earlier thread? If so, the problem I think you are having is that you never identified the cause of this error. And so that will continue to be a problem until you identify the cause and fix it. Marking the answer correct doesn't mean you have found the cause.

Re: How to conditionally assign a library on a unix server

PaulMcDonald-AZ — Thu, 17 Apr 2025 21:28:04 GMT

The LIBREF() function verifies that a libref has been assigned. If the libref is assigned, then it returns a 0; if not assigned then it returns a nonzero value.

From your code, it seems to me that you are wanting to check to see if a LIBREF has been assigned, and if not then assign it. You might try something like this:

%macro testlibref (libref, path) ;
%local libref path rc ;

%if %sysfunc(libref(&libref)) %then %let rc = %sysfunc(libname(&libref, &path) ;

%mend testlibraf ;

/* UNIX example */
%testlibref (MYLIB, /my/test/library) ;

/*Windows example */
%testlibref (MYLIB, c:\my\test\library) ;

Or you may prefer a data step to accomplish this, it can provide a little stronger control of quotes and things:

/* UNIX example */
data _null_ ;
if libref('/my/test/library') then call execute ("libname MYLIB '/my/test/library' ;") ;
run ;

/* Windows example */
data _null_ ;
if libref(''c:\my\test\library') then call execute ("libname MYLIB 'c:\my\test\library' ;") ;
run ;

Re: How to conditionally assign a library on a unix server

Ksharp — Fri, 18 Apr 2025 01:49:12 GMT

You could use libname() funtion in data step to get job done.



data _null_;
response =libref("data");
put response=;
if response ne 0 then rc=libname('data','c:\temp');
run;