1. To list the contents of SAR files.
SAPCAR -tvf <your-SAR-file>
2. To extract SAR files.
SAPCAR -xvf <your-SAR-file>
3. To compress files to SAR files.
SAPCAR -cvf <your-SAR-file> <file-to-compress>
Source: http://itsiti.com/list-extract-compress-using-sapcar