Bash equivalent of Python's shlex.quote

Solution 1:

Since you refer to bash, you can use the bash specific format character "q" in printf:

$ printf '%q\n' "The world is fuiled by \$s isn't it?" 
The\ world\ is\ fuiled\ by\ \$s\ isn\'t\ it\?

From the documentation on bash:

%q
Causes printf to output the corresponding argument in a format that can be reused as shell input.

https://www.gnu.org/software/bash/manual/html_node/Bash-Builtins.html

Solution 2:

Or using @Q variable expansion

cat generate_greeting_script:

#!/usr/bin/env bash

cat >greet <<HEREDOC
#!/usr/bin/env bash

printf ${1@Q}' %s!\n' "\$USER"
HEREDOC
chmod +x greet

./generate_greeting_script 'I say hello to'

A .sh extension on executable scripts with a shebang is not required.

Generated greet:

#!/usr/bin/env bash

printf 'I say hello to'' %s!\n' "$USER"

Output:

./greet
I say hello to lea!

Reference man bash:

${parameter@operator}

Parameter transformation.

The expansion is either a transformation of the value of parameter or information about parameter itself, depending on the value of operator. Each operator is a single letter:

Q

The expansion is a string that is the value of parameter quoted in a format that can be reused as input.

Solution 3:

I think you're looking Bash-specific printf %q format specifier:

$ read &&  printf "%q\n" "$REPLY"
"very*complicated_&&;$stuff--string'""""'"<<!!
\"very\*complicated_\&\&\;\$stuff--string\'\"\"\"\"\'\"\<\<\!\!
$ echo \"very\*complicated_\&\&\;\$stuff--string\'\"\"\"\"\'\"\<\<\!\!
"very*complicated_&&;$stuff--string'""""'"<<!!