cs107-lecture-examples

Example codes used during Harvard CS107 lectures
git clone https://git.0xfab.ch/cs107-lecture-examples.git
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redirections.sh (773B)


      1 #!/usr/bin/env bash
      2 # File       : redirections.sh
      3 # Description: Some redirection examples for stdout and stderr
      4 # Copyright 2022 Harvard University. All Rights Reserved.
      5 
      6 echo 'The `echo` command outputs to stdout:'
      7 echo 'Hello CS107/AC207'
      8 echo 'Hello CS107/AC207' >/dev/null # no output to stdout here
      9 
     10 echo 'The `cp` command takes at least two arguments:'
     11 
     12 cp >out1 # this will fail and print an error message on your screen.  The stdout
     13          # stream will be empty and so is the file out1
     14 
     15 cp 2>/dev/null  # this will redirect the stderr stream into /dev/null.  You will
     16                 # not see the error message on your screen
     17 
     18 cp >out2 2>&1  # this will redirect both stdout and stderr to the file out2.
     19                # There will be no output on the screen