Linux/BASH

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Revision as of 10:18, 21 January 2021 by Marcluer (talk | contribs) (→‎If)
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Shebang

  • #!/bin/bash

Output & Piping

  • output to file
command > file.txt             # redirect output
command >> file.txt            # append to file

command &> file.txt            # stdout and stderr to file
command &>> file.txt           # stdout and stderr append to file

command 2> file.txt            # stderr to file
command 2>> file.txt           # stderr append to file

command | tee -a file.txt      # stdout to terminal and file (append)
command |& tee -a file.txt     # stdout+stderr to terminal and file (append)

redirecting output

command 2>&1 >/dev/null # stderr to stdout and stdout to null

If

if [ condition ]
  then command1
  else command2
fi
if [ -f file.txt ]; then echo "file exists"; fi

For loop

for OUTPUT in $(linuxcommand)
do
	command1 on $OUTPUT
	command2 on $OUTPUT
	commandN
done

Links