Efficient Directory Management in SAS: A Custom Macro
Managing directories effectively is crucial for organizing and handling large volumes of files in SAS. In this article, we’ll walk through a custom SAS macro that helps you identify all folders within a specified directory. This macro is particularly useful for managing directory structures in complex projects.
Macro Overview
The get_folders macro is designed to list all folders present in a specified directory. It verifies the existence of the directory, retrieves the names of all items within it, and outputs this information in a readable format. Below is the complete SAS code for this macro:
%macro get_folders(dir);
/*
Macro: get_folders
Purpose: Identifies all folders available within a specified directory location.
Source: Custom macro developed for directory management in SAS.
Date: September 2024
*/
/* CHECK FOR EXISTENCE OF DIRECTORY PATH */
%if %sysfunc(fileexist(&dir)) %then %do;
/* ASSIGNS THE FILEREF OF MYDIR TO THE DIRECTORY AND OPENS THE DIRECTORY */
%let filrf=mydir;
%let rc= %sysfunc(filename(filrf,&dir));
%let did= %sysfunc(dopen(&filrf));
/* RETURNS THE NUMBER OF MEMBERS IN THE DIRECTORY */
%let memcnt= %sysfunc(dnum(&did));
%put rc=&rc;
%put did=&did;
%put memcnt=&memcnt;
data Dir_Contents;
length member_name $ 32;
/* LOOPS THROUGH ENTIRE DIRECTORY */
%do i = 1 %to &memcnt;
member_name="%qsysfunc(dread(&did,&i))";
put 'member_name ' member_name;
output;
%end;
run;
TITLE "CONTENTS OF FOLDER &DIR";
proc print data=dir_contents;
run;
/* CLOSES THE DIRECTORY */
%let rc= %sysfunc(dclose(&did));
%end;
%else %do;
%put ERROR: Folder &dir Not Found;
%end;
%mend get_folders;
/* Example usage of the macro */
%get_folders('/example/directory/path');
How It Works
Here’s a step-by-step breakdown of the macro:
- Check Directory Existence: The macro first checks if the specified directory exists using the
%sysfunc(fileexist)function. If the directory does not exist, an error message is displayed. - File Reference and Directory Opening: If the directory exists, a file reference is assigned, and the directory is opened using the
%sysfunc(filename)and%sysfunc(dopen)functions. - Count Directory Members: The macro retrieves the number of items (folders or files) in the directory with
%sysfunc(dnum). - Retrieve and Output Folder Names: Using a data step, the macro loops through each item in the directory, retrieves its name with
%qsysfunc(dread), and outputs this information to a dataset. - Display Contents: The contents of the dataset are printed using
PROC PRINT. - Close the Directory: Finally, the directory is closed with
%sysfunc(dclose).
Usage Example
To use this macro, simply call it with the directory path you want to scan:
%get_folders('/example/directory/path');This will list all folders within the specified directory, making it easier to manage and organize your files.
Conclusion
The get_folders macro is a powerful tool for directory management in SAS. By incorporating this macro into your workflow, you can streamline the process of identifying and organizing folders within your projects. Feel free to modify and adapt the macro to suit your specific needs.
Happy coding!