Which command is commonly used to view Unix-like file permissions and the associated owner/group information?

Which command is commonly used to view Unix-like file permissions and the associated owner/group information?

• A. ls -l
• B. cat /etc/passwd
• C. rm -rf
• D. ps aux

Answer: (A)

Showing who can do what with a file and who owns it is done with a long listing. The command that prints a detailed listing including permissions and the owner/group is ls -l. Each line begins with a permission string like -rw-r----- or drwxr-xr-x, where the first character indicates the file type and the next nine characters are split into three groups for user, group, and others. These tell you at a glance whether the owner, members of the group, or others can read, write, or execute. Right after that, you see the owner and the group names, so you know who owns the file and which group it’s associated with. This is why ls -l is the standard way to view file permissions and ownership. Contrast: cat /etc/passwd shows user account information, rm -rf deletes files and directories, and ps aux lists running processes. So the best choice for viewing permissions and owner/group is ls -l.

Showing who can do what with a file and who owns it is done with a long listing. The command that prints a detailed listing including permissions and the owner/group is ls -l. Each line begins with a permission string like -rw-r----- or drwxr-xr-x, where the first character indicates the file type and the next nine characters are split into three groups for user, group, and others. These tell you at a glance whether the owner, members of the group, or others can read, write, or execute. Right after that, you see the owner and the group names, so you know who owns the file and which group it’s associated with. This is why ls -l is the standard way to view file permissions and ownership.

Contrast: cat /etc/passwd shows user account information, rm -rf deletes files and directories, and ps aux lists running processes. So the best choice for viewing permissions and owner/group is ls -l.