Which permissions are set on a regular file once the permissions have been modified with the command chmod 654 file.txt?

When modifying file permissions with the command chmod 654 file.txt, the numeric mode corresponds to specific permissions assigned to the user, group, and others for a regular file.

In the numeric permission system:

• The first digit (6) defines the permissions for the user. The value 6 corresponds to read (4) and write (2) permissions combined, resulting in rw-.

• The second digit (5) defines the permissions for the group. The value 5 corresponds to read (4) and execute (1) permissions combined, resulting in r-x.

• The third digit (4) defines the permissions for others. The value 4 corresponds to read (4) only, resulting in r--.

When these values are combined, the resulting permission string is:

• User: rw- (read and write)

• Group: r-x (read and execute)

• Others: r-- (read only)

Thus, the correct permissions set on the file after the command is executed will be represented as -rw-r-xr--. This string provides a clear view of the permissions assigned to the user, group, and others for the regular file.