|GNU Bash Reference Manual|
by Chet Ramey and Brian Fox
Paperback (6"x9"), 180 pages
RRP £19.95 ($29.95)
"An essential resource .... the most detailed coverage available for all aspects of Bash" --- Linux User and Developer Magazine (Issue 37, Mar 2004) Get a printed copy>>>
3.1.1 Shell Operation
The following is a brief description of the shell's operation when it reads and executes a command. Basically, the shell does the following:
Reads its input from a file (see section 3.8 Shell Scripts), from a string
supplied as an argument to the
-cinvocation option (see section 6.1 Invoking Bash), or from the user's terminal.
Breaks the input into words and operators, obeying the quoting rules
described in section 3.1.2 Quoting. These tokens are separated by
metacharacters. Alias expansion is performed by this step (see section 6.6 Aliases).
- Parses the tokens into simple and compound commands (see section 3.2 Shell Commands).
- Performs the various shell expansions (see section 3.5 Shell Expansions), breaking the expanded tokens into lists of filenames (see section 3.5.8 Filename Expansion) and commands and arguments.
- Performs any necessary redirections (see section 3.6 Redirections) and removes the redirection operators and their operands from the argument list.
- Executes the command (see section 3.7 Executing Commands).
- Optionally waits for the command to complete and collects its exit status (see section 3.7.5 Exit Status).
|ISBN 0954161777||GNU Bash Reference Manual||See the print edition|