YULI NURACHMAN

Example 1: Executing Operating System Commands Conditionally If you want to execute operating system commands conditionally, use the CALL SYSTEM routine: options noxwait; data _null_; input flag $ name $8.; if upcase(flag)='Y' then do; command='md c:\'||name; call system(command); end; cards; Y mydir Y junk2 N mydir2 Y xyz ; This example uses the value of the variable FLAG to conditionally create directories. After the DATA step executes, three directories have been created: C:\MYDIR, C:\JUNK2, and C:\XYZ. The directory C:\MYDIR2 is not created because the value of FLAG for that observation is not Y . The X command is a global SAS statement. Therefore, it is important to realize that you cannot conditionally execute the X command. For example, if you submit the following code, the X statement is executed: data _null_; answer='n'; if upcase(answer)='y' then do; x 'md c:\extra'; end; run; In this case, the directory C:\EXTRA is created regardless of whether the value of ANSWER is equal to 'n' or 'y' .