My CLI cheatsheet

This page is a little cheat sheet for commands that I use often, but don't always remember well enough to get right on the first try.

Changing file permissions

get a list of all files in directory that contain a string:
```
grep -l '<string>' *.*
```
search all files in a directory for a string and output the file name and line the string appears in to a file in the parent directory *:
```
grep -Eir '<string>' . >> ../<output_file>
```
get all lines in file that don't contain a string and output to a file in the parent directory *:
```
cat <input_file> | grep -v '<string>' >> ../<output_file>
```
show the differences between two files with side by side output:
```
diff -y <file_1> <file_2>
```

* outputting to the same directory results in grepping the file you're writing to. You don't want that.

scp a file from my local machine to a server:
```
scp <file_name> <user>@<ip_address>:
```

scp a file from a server to my local machine:

scp <user>@<ip_address>:<file_name> <file_name>

search and replace text in all files in directory:
```
sed -i.bak 's/<text_to_replace>/<new_text>/g' *
```

search and replace text in all files of one type in a directory recursively:

find . -type f -name "*.<ext>" -exec sed -i.bak 's/<text_to_replace>/<new_text>/g' {} +

delete the backup files after running one of those sed commands:
```
find . -name '*.bak' -delete
```

Prepend and append text to all lines in a file:

awk '{ print "<prepend_text>", $0, "<append_text>" }' <input_file> > <output_file>

find all files with given extension recursively:
```
find . -type f -name "*.<ext>"
```
list all files in a directory, including hidden files:
```
ls -a
```
list all files in a directory in one column:
```
ls -1
```
list all files in a directory with a specific extension:
```
ls *.<ext> or ls *.{<ext_1>,<ext_2>}
```