Introduction to Unix

2.6. Special characters

Linux for Programmers and Users, Section 3.7

<Cntrl-c>

cancel running program or partially entered commmand line

<Cntrl-d>

end of file (eof)

2.7. passwd

Linux for Programmers and Users, Section 3.8

passwd

Change the login password.

SYNOPSIS

passwd

2.8. Logging Out

Linux for Programmers and Users, Section 3.9

You may log out of a shell either by typing exit or pressing <Cntrl-d>.

The later may suprise you since <Cntrl-d> sends the end of file character. However, this is consistent if you consider that when the shell is executing a shell script, it is reading commands from a file and exits when the eof character is detected.