This macro uses the UNIX command ENV in a FILENAME PIPE along with various other SAS functions to retrieve a list of all environment variables. The list is checked against the environment variable passed to the macro. If the variable is found, the word yes is returned. If the variable is not found, the word no is returned.

This is for the UNIX operating system.

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These sample files and code examples are provided by SAS Institute Inc. "as is" without warranty of any kind, either express or implied, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Recipients acknowledge and agree that SAS Institute shall not be liable for any damages whatsoever arising out of their use of this material. In addition, SAS Institute will provide no support for the materials contained herein.

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/** This particular test checks to see if the environment variable logname **/
/** exist. Just replace logname in the macro call with the environment     **/
/** variable you want to check and yes will be returned if it exist, else  **/
/** no is returned.                                                        **/

%macro check(var);
 %let filref=myenv;
 %let dsid=%sysfunc(filename(filref,env,pipe,lrecl=32767));
 %let fid=%sysfunc(fopen(&filref,s));
  %do %while(%sysfunc(fread(&fid)) = 0);
     %let rc=%qsysfunc(fget(&fid,c));
     %let temp=%scan(%superq(c),1,=);
     %if %upcase(&temp)=%upcase(&var) %then %do;
       %let flag=1;
       %goto exit;
     %end;
     %else %let flag=0;
  %end;
 %exit:
 %let rc=%sysfunc(fclose(&fid));
 %let rc=%sysfunc(filename(filref));
  %if &flag=1 %then yes;
  %else no;
%mend check;

%put Does env var exist: %check(logname);

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These sample files and code examples are provided by SAS Institute Inc. "as is" without warranty of any kind, either express or implied, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Recipients acknowledge and agree that SAS Institute shall not be liable for any damages whatsoever arising out of their use of this material. In addition, SAS Institute will provide no support for the materials contained herein.

/** log results **/

Does env var exist: yes

This macro enables you to check for the existence of a system environment variable on UNIX.

Type:

Sample

Date Modified:	2011-06-29 10:51:16
Date Created:	2011-06-28 08:58:36

Operating System and Release Information

Product Family	Product	Host	SAS Release
			Starting	Ending
SAS System	Base SAS	HP-UX IPF
		IRIX
		HP-UX
		AIX
		64-bit Enabled Solaris
		ABI+ for Intel Architecture
		64-bit Enabled HP-UX
		64-bit Enabled AIX
		Linux
		Linux for x64
		Linux on Itanium
		OpenVMS Alpha
		OpenVMS on HP Integrity
		Solaris
		Solaris for x64
		Tru64 UNIX