Linux in a Nutshell, Fifth Edition

Syntax | 627

Bash and Korn

This is the Title of the Book, eMatter Edition

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

Special Files

Both shells read one or more startup files. Some of the files are read only when a

shell is a login shell.

The Korn shell reads these files:

1. /etc/profile. Executed automatically at login, first.

2. ~/.profile. Executed automatically at login, second.

3. $ENV. Specifies the name of a file to read when a new Korn shell is created.

(ksh88: all shells, ksh93: interactive shells only.) The value is a variable

(ksh93: and command and arithmetic) substituted in order to determine the

actual filename. Login shells read $ENV after processing /etc/profile and

$HOME/.profile.

Bash reads these files:

1. /etc/profile. Executed automatically at login, first.

2. The first file found from this list: ~/.bash_profile, ~/.bash_login,or~/.profile.

Executed automatically at login, second.

3. ~/.bashrc is read by every shell, after the login files. However, if invoked as sh,

Bash instead reads $ENV, just as the Korn shell does.

For both shells, the getpwnam( ) and getpwuid( ) functions are are the sources of

home directories for ~name abbreviations. (On single-user systems, the user data-

base is stored in /etc/passwd. However on networked systems, this information

may come from NIS, NIS+, or LDAP—not your workstation password file.)

Filename Metacharacters

In the Korn ...