Sams Teach Yourself UNIX® in 24 Hours Second Edition

Summary

In this hour, you learned the basics of UNIX file permissions, including how to set and modify file permissions with chmod and how to analyze file permissions as shown by the ls -l command. You also learned about translating between numeric bases (binary and decimal) and how to convert permissions strings into numeric values. Both are foundations for the umask command, which you learned to interpret and alter as desired.