Temporary edit a command

[riless]

Sometimes I'd like to edit a command in my menu before running it.

Some cases where it could happen.

• Replace a hostname by an IP address (because hostname cannot be resolved)
• Edit a parameter in the predefined command (ssh user@hostname watch -n5 nvidia-smi -> ssh user@hostname watch -n1 nvidia-smi
• etc.

Proposal Add a combination key (Alt+) to show command in rather that running it.

[julienmoumne]

Thanks for submitting this issue.

This is definitely a useful feature to have.

Two ideas that come to my mind to implement it, either

• enter "bash" mode and pre-populate it with the selected command
• integrate a readline library such as chzyer/readline or sahib/readline

[julienmoumne]

In the meantime, here are workarounds that I often use :

Edit a parameter in the predefined command (ssh user@hostname watch -n5 nvidia-smi -> ssh user@hostname watch -n1 nvidia-smi

A script can be used to take the watch interval as a parameter or prompt for a value if not provided :

#./watch-nvidia-smi.sh

INTERVAL=$1
if [ -z "${INTERVAL}" ]; then
    echo -n "Watch interval: "; read INTERVAL
fi

ssh user@hostname watch -n$INTERVAL nvidia-smi

The script can then be used several ways :

item({key: 'p', desc: 'prompt for interval', cmd: './watch-nvidia-smi.sh'})
item({key: '1', desc: 'interval = 1', cmd: './watch-nvidia-smi.sh 1'})
item({key: '2', desc: 'interval = 2', cmd: './watch-nvidia-smi.sh 2'})

Instead of prompting for a value, a default one can be hard-coded :

#./watch-nvidia-smi-wo-prompt.sh

ssh user@hostname watch -n${1:-5} nvidia-smi

item({key: 'd', desc: 'default interval (=5)', cmd: './watch-nvidia-smi-wo-prompt.sh'})
item({key: '1', desc: 'interval = 1', cmd: './watch-nvidia-smi-wo-prompt.sh 1'})
item({key: '2', desc: 'interval = 2', cmd: './watch-nvidia-smi-wo-prompt.sh 2'})

Replace a hostname by an IP address (because hostname cannot be resolved)

This one depends on your actual use case.

Are you trying to connect to a SSH server where its hostname and ip address rotates amongst a known set of values? In that case, here is a script that tries to connect to a set of addresses in turn until it succeeds :

#ssh-with-fallback.sh

addrs=(unknown-hostname 127.0.0.1 localhost)

for addr in "${addrs[@]}"
do
  if ssh $addr; then
    break
  fi
done