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The echo
command does one simple job: it prints to the output the argument passed to it.
This example:
echo "hello"
will print hello
to the terminal.
We can append the output to a file:
echo "hello" >> output.txt
We can interpolate environment variables:
echo "The path variable is $PATH"
Beware that special characters need to be escaped with a backslash \
. $
for example:
This is just the start. We can do some nice things when it comes to interacting with the shell features.
We can echo the files in the current folder:
echo *
We can echo the files in the current folder that start with the letter o
:
echo o*
Any valid Bash (or any shell you are using) command and feature can be used here.
You can print your home folder path:
echo ~
You can also execute commands, and print the result to the standard output (or to file, as you saw):
echo $(ls -al)
Note that whitespace is not preserved by default. You need to wrap the command in double quotes to do so:
You can generate a list of strings, for example ranges:
echo {1..5}
The
echo
command works on Linux, macOS, WSL, and anywhere you have a UNIX environment
Download my free Linux Commands Handbook
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More cli tutorials:
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- Linux commands: rmdir
- Linux commands: ls
- Linux commands: mv
- Linux commands: cp
- Linux commands: less
- Linux commands: tail
- Linux commands: touch
- Linux commands: cat
- Linux commands: find
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- Linux commands: ps
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- Linux commands: top
- Linux commands: kill
- Linux commands: killall
- Linux commands: alias
- Linux commands: jobs
- Linux commands: bg
- Linux commands: fg
- Linux commands: type
- Linux commands: which
- Linux commands: whoami
- Linux commands: who
- Linux commands: clear
- Linux commands: su
- Linux commands: sudo
- Linux commands: chown
- Linux commands: chmod
- Linux commands: passwd
- Linux commands: open
- Linux commands: wc
- Linux commands: history
- Linux commands: du
- Linux commands: umask
- Linux commands: grep
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- Linux commands: nohup
- Linux commands: df
- Linux commands: xargs
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- Linux commands: gunzip
- Linux commands: ping
- Linux commands: traceroute
- Linux commands: tar
- Linux commands: export
- Linux commands: crontab
- Linux commands: dirname
- Linux commands: basename
- Linux commands: printenv
- Linux commands: env
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- A short guide to emacs
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