musteresel's blog

Specify a password command line argument interactively in Bash


tagged: bash

Today I had to download a file to a server I was connected to via ssh:

# ...
# HTTP request sent, awaiting response... 401 Unauthorized
# Username/Password Authentication Failed.

The server I was running this on isn’t “mine” and thus cannot be trusted, thus I didn’t want to just specify --user=USERNAME and --password=PASSWORD on the command line as it would end up in at least the bash history and possibly other places, from where I’d need to delete it.

A IMO better way is to specify username and password interactively to the shell, using the read builtin:

wget \
  --user=`read -p 'username:'; echo $REPLY` \
  --password=`read -s -p 'password'; echo $REPLY`

Command substitution (the backticks around the command) invokes a subshell, in which the read is performed. read assigns the input to the variable REPLY, which I echo to standard output such that the invoking shell substitutes the command with this output.