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  BASH Programming培訓

The simplest script
Choosing the shell (magic number #!, Sha-bang)
Calling the script
External and built-in commands
Some special characters
Comment (#)
End of Line (;)
An empty statement (:)
Redirection of input output (>, <, >>)
Redirecting output
Redirection of input
Stream (|)
Start the process in the background (&)
Variables and Parameters
Destruction of variables (unset)
Variable with a null value
Save the result to a variable (backquotes ``)
Parameters request ($ 0, $ #, $ 1, $ 2, $ 3 ...)
Manual shift
Quoting.
Escape character (\)
Regular Expressions
Conditional statements
The if / then
The if / then / else
Nesting if statements
The if / elif
case statement
Operators
Operators and, or (&&, | |)
test command
Completing scrypt
The exit statement

Use the status of completion of the program in a script ($?)

Tests and Operators
Operators text file
Tests the file type
Test file attributes
Comparison operators
Comparing arithmetic using the command if
Integer comparison operators
Comparing strings
Comparing the complex (and, or)
Nesting comparison operators
The assignment operator
Arithmetic operators
Operators operations on bits (bitwise operators)
Logical operators
Numeric constants
Loopa
The loop for / in
The command seq
The while loop
Loop until
Controlling the loop (break, continue)
Text Processing
Command head, tail
Sort, Uniq, Expand, Unexpand
Cut, Paste, Join, Wc,Tr
Text search (grep)

Stream Editor (sed)

Interactive programs

Read command
User select
Features

Sleep command

If the script does not work? (debugging)