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How to execute a bash command stored as a string with quotes and asterisk [duplicate]

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What does %% mean in bash?

So as far as I can tell, %% doesn't have any special meaning in a bash function name. It would be just like using XX instead. This is despite the definition of a name in the manpage: name A word consisting only of alphanumeric characters and under- scores, and beginning with an alphabetic character or an under- score.

What is exec $@ in bash?

On Unix-like operating systems, exec is a builtin command of the Bash shell. It lets you execute a command that completely replaces the current process. The current shell process is destroyed, and entirely replaced by the command you specify.

What is $() called in bash?

It turns out, $() is called a command substitution.


Have you tried:

eval $cmd

For the follow-on question of how to escape * since it has special meaning when it's naked or in double quoted strings: use single quotes.

MYSQL='mysql AMORE -u username -ppassword -h localhost -e'
QUERY="SELECT "'*'" FROM amoreconfig" ;# <-- "double"'single'"double"
eval $MYSQL "'$QUERY'"

Bonus: It also reads nice: eval mysql query ;-)


Use an array, not a string, as given as guidance in BashFAQ #50.

Using a string is extremely bad security practice: Consider the case where password (or a where clause in the query, or any other component) is user-provided; you don't want to eval a password containing $(rm -rf .)!


Just Running A Local Command

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
"${cmd[@]}"

Printing Your Command Unambiguously

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf 'Proposing to run: '
printf '%q ' "${cmd[@]}"
printf '\n'

Running Your Command Over SSH (Method 1: Using Stdin)

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf -v cmd_str '%q ' "${cmd[@]}"
ssh other_host 'bash -s' <<<"$cmd_str"

Running Your Command Over SSH (Method 2: Command Line)

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf -v cmd_str '%q ' "${cmd[@]}"
ssh other_host "bash -c $cmd_str"

try this

$ cmd='mysql AMORE -u root --password="password" -h localhost -e "select host from amoreconfig"'
$ eval $cmd

You don't need the "eval" even. Just put a dollar sign in front of the string:

cmd="ls"
$cmd