https://communities.sas.com/t5/SAS-Programming/Can-you-tell-me-what-this-means-thanks/m-p/11201#M1006 It is exist function, you can read more about that in <A href="http://support.sas.com/documentation/cdl/en/lrdict/63026/HTML/default/viewer.htm#a000210903.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrdict/63026/HTML/default/viewer.htm#a000210903.htm</A> Tue, 05 Oct 2010 06:00:07 GMT ieva 2010-10-05T06:00:07Z https://communities.sas.com/t5/SAS-Programming/Can-you-tell-me-what-this-means-thanks/m-p/11200#M1005 %IF <B>%SYSFUNC</B> ( <B>EXIST</B>(MYLIB.CONTROLS)) = 1 <BR /> %THEN %DO; <BR /> PROC DATASETS LIBRARY=mylib NOLIST; <BR /> DELETE CONTROLS; <BR /> RUN; <BR /> %END; <BR /> I'm a newer, I only know <B>%SYSFUNC</B> function for automatic macro variables likes sysdate9; how THATcan be used with A data file ((MYLIB.CONTROLS),<BR /> AND what means for <B>EXIST</B>?<BR /> THANKS A MILLION IN ADVANCE.<BR /> SASJUNIOR Tue, 05 Oct 2010 02:12:39 GMT https://communities.sas.com/t5/SAS-Programming/Can-you-tell-me-what-this-means-thanks/m-p/11200#M1005 deleted_user 2010-10-05T02:12:39Z https://communities.sas.com/t5/SAS-Programming/Can-you-tell-me-what-this-means-thanks/m-p/11201#M1006 It is exist function, you can read more about that in <A href="http://support.sas.com/documentation/cdl/en/lrdict/63026/HTML/default/viewer.htm#a000210903.htm" target="_blank">http://support.sas.com/documentation/cdl/en/lrdict/63026/HTML/default/viewer.htm#a000210903.htm</A> Tue, 05 Oct 2010 06:00:07 GMT https://communities.sas.com/t5/SAS-Programming/Can-you-tell-me-what-this-means-thanks/m-p/11201#M1006 ieva 2010-10-05T06:00:07Z