Chapter VIM editor and script SHELL Day 4 July 17

• VIM editor and script SHELL
• Because Linux everything is a file system, so editing the file is to configure the service.
• Three modes VIM editor
  • Command Mode
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  • Input Mode
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  • Line mode
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• Three small practice, practice hand to configure the service.
  • Essence: VIM with accurate set of parameters, and know the effect of each parameter for use.
• Two operation modes SHELL script.
  • Interactive (interactive): a command input immediately after execution.
  • Batch (Batch): Complete the entire script execution.
• How SHELL Scripting
  • Ending in .sh
  • The first line declares #! / Bin / bash
  • # After just a comment, no other action.
  • Then take command.
  • How to perform? bash script
• SHELL script can accept user run-time parameters
  • For example, $ 0 corresponds to the name of the current Shell script, and $ # corresponds to the total number of parameters, $ * corresponds to the parameter values ​​for all locations, $? Corresponds to display a command return value, and $ 1, $ 2, $ 3 ...... parameter values ​​respectively corresponding to the N-th position.
• Grammar test conditions
  • [Conditional expression] have a space before and after #
  • Success will return the number 0, otherwise it returns other random number.
  • classification
    • File test statement [-d / etc / fstab]
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    • Statement logic test
    • Integer value comparison statements
    • String comparison statement