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Linux is an operating system that many developers will use.
Therefore, it’s a good idea to learn some Linux commands.
In this article, we’ll look at some useful Linux commands we should know.
xargs
The xargs
command lets us pass output of a command and use it as an argument to another command.
The general syntax is:
command1 | xargs command2
For instance, we can write:
cat deleteall.txt | xargs rm
to the file paths in deleteall.txt
to the rm
command to delete all the files listed in deleteall.txt
.
With the -p
switch, we see a confirmation prompt before the command is run:
cat deleteall.txt | xargs -p rm
We can run multiple commands with the -I
switch:
command1 | xargs -I % /bin/bash -c 'command2 %; command3 %'
The commands are the ones after the %
.
df
The df
command lets us get disk usage information.
We can use the -h
switch to get the values in a human-readable format.
nohup
The nohup
command lets us run a command that doesn’t end when the terminal is killed.
We just put the command after nohup
to run it.
diff
diff
lets us compare the content of 2 text files.
For example, we run:
diff dogs.txt dogs2.txt
to compare the content of dogs.txt
and dogs2.txt
.
The -y
switch will make diff
compare the 2 files line by line.
We can also use it to compare directories with the -r
switch:
diff -r dir1 dir2
We can compare which files differ with the r
and q
switches together:
diff -rq dir1 dir2
uniq
The uniq
command lets us get unique lines of text from a file.
For instance, we run:”
uniq dogs.txt
to get the unique lines of text from the dogs.txt
file.
We can also use it to get unique lines of output from a command with the |
operator:
ls | uniq
We can sort the lines before getting the unique lines with the sort
command:
sort dogs.txt | uniq
We can display only the duplicate lines with the -d
switch:
sort dogs.txt | uniq -d
The -u
switch makes it only display the unique lines:
sort dogs.txt | uniq -u
The -c
switch lets us count the occurrences of each line:
sort dogs.txt | uniq -c
sort
The sort
command lets us sort lines of text or text command outputs.
For example, we run:
sort dogs.txt
to sort the lines in dogs.txt
.
We can use the -r
switch to sort the items in reverse order:
sort -r dogs.txt
And we can use the -u
switch to return only the unique lines:
sort -u dogs.txt
We can also use sort
to sort command outputs.
For instance, we can sort the output from the ls
command with:
ls | sort
Conclusion
We can pass arguments to commands, and diff and manipulate text outputs with various Linux commands.
Top comments (2)
Nice post!
Thanks