Linux in a Nutshell, Fifth Edition

sum | 453

Linux

Commands

This is the Title of the Book, eMatter Edition

Copyright © 2006 O’Reilly & Associates, Inc. All rights reserved.

-p promptstring

Use the specified promptstring to prompt for a password. The

string may contain the following escape codes, which will be

replaced with the current user’s login name and local

hostname.

%h Local hostname without the domain name.

%H Local hostname with the domain name.

%u Current user’s login name

%U Login name of the user the command will run under. The

default is root.

%% A single percent (%) character.

-s Run the shell specified in the SHELL environment variable, or

the default shell specified in /etc/passwd. If a command is

given, it should be a shell script and not a binary file.

-u user

Run command as the specified user instead of the root user.

This may also be specified as a user ID number using #uid.

-v Update timestamp for user. Prompt for password if necessary.

-H Set the HOME environment variable to the home directory of

the target user.

-K Remove user’s timestamp.

-L List parameters that may be set as defaults for a user in the /etc/

sudoers file.

-P Preserve initial user’s group membership.

-S Read password from standard input instead of from the

console.

-V Print version number, then exit. When run by the root user,

print sudo’s defaults and the local network address as well.

-- Stop reading command-line arguments.

sum

sum [options] files

Calculate ...