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Author: Quentin McMullen
As a SAS programmer, I am dependent on my SAS autocall macro library. It stores a bunch of utility macros that I use on a daily basis. When I started learning about stored processes and other BI tools, one of my first thoughts was “How can I access all of my utility macros?” And it turns out, it’s pretty straight forward to define an autocall library in a SAS BI setting. And the best part is, you don’t have to be a SAS administrator or modify SAS configuration files. You can do it with just a single line of code.
What’s An SAS Autocall Macro Library?
Autocall libraries are one way to make SAS macros easily accessible. Suppose you have a bunch of macros, and you want to be able to invoke them in a program. You could paste all of the macro definitions into your program, or if you have each macro definition stored in its own .sas file, you could %INCLUDE each file. But it is easier to create an autocall library. To create an autocall library, you:
- Store each macro in a .sas file with the same name as the macro. So the definition of %MyMacro is stored in the file mymacro.sas.
- Store all of the .sas files with macro definitions in a single directory, call it /MyAutocallMacros.
- Tell SAS to look in /MyAutocallMacros when looking for macro definitions.
Once you have defined an autocall library, all of the macros stored inside it are available to your program. If you invoke a macro that has not been previously compiled, SAS will look in the autocall library for the definition, compile it, and execute it.
Even if you have never created an autocall library, you already have one. SAS provides a suite of autocall macros by default. If you use stored processes, you probably use %STPBEGIN / %STPEND. While they may seem like magic, they are just autocall macros. If you search around your server, you’ll find stpbegin.sas and stpend.sas, with the definition of each macro.
How To Point To An Autocall Library
As with most things SASsy, there are many ways to point to an autocall library. If you are an administrator for your SAS server, there are a plethora of configuration and autoexec files that would allow you to point to the library. If you are a developer, I think the easiest way to point to an autocall library is adding an options statement to your code:
options insert=(sasautos="/MyAutocallMacros") ;
When you run that, the directory /MyAutocallMacros will be added to the front of the search path for autocall macros. I put that line near the top of all of my stored processes. I also put it near the top of all of my DI Studio jobs, and in Enterprise Guide I automatically run it every time I connect to a server. Once it has run, my entire macro library is available for use.
Is It Really That Easy?
Yes. For the most part…
There are two possible gotchas worth mentioning.
If your code is running on a Linux/Unix server, make sure the file names of macros stored in your autocall library are all lowercase. File names are case-sensitive in *nix. If the definition of %MyMacro is stored in MyMacro.sas, the autocall facility will not be able to find it. The file must be named mymacro.sas. Years ago I lost about half a day when I was bit by that problem, trying to figure out why half of my autocall macros wouldn’t work.
Regardless of the operating system, it is essential that when your SAS code executes, it can read the macro definitions stored in your autocall library. When using PC SAS or SAS Enterprise Guide, this is rarely an issue. If you wrote the .sas files in your library, you can read them. If users don’t have read access, the macros are not found. But as a BI developer, you are probably creating stored processes and other tools that will be executed by other users. When a user runs the code, that user must have read access at the operating system level to read the .sas files in the autocall library (some stored processes run under a service account such as SASSRV, in which case the service account must have read access). If they don’t have read access, the macro definitions will not be found. So check the permissions on the files in your autocall library to make sure they are readable by your users. Sometimes it’s acceptable just to make your autocall library readable by “world.”
Want More?
If you want to learn more about autocall libraries (or any macro language topics), I would whole-heartedly recommend you buy a copy of Art Carpenter’s excellent book, Carpenter’s Complete Guide to the SAS Macro language. Of course, user group papers are always a great resource as well. Searching LEXJANSEN.COM for autocall macros will turn up a number of helpful papers, including (hopefully) a paper I wrote on an automated method to generate documentation of the content of an autocall library.
What Say You?
Do you use autocall libraries in SAS BI tools you develop? Feel free to share any tips you have on using a macro library. Especially if you have thoughts on how I could be doing this better!
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Post Using an Autocall Macro Library in SAS BI appeared first on Business Intelligence Notes for SAS® BI Users. Written by Quentin McMullen. Go to Business Intelligence Notes for SAS® BI Users to subscribe.
This post was kindly contributed by Business Intelligence Notes for SAS® BI Users - go there to comment and to read the full post. |