LINUX HACK 30

Hack 30. PS2 - Continuation Interactive Prompt

A very long command can be broken down to multiple lines by giving \ at the end of the line. The default interactive prompt for a multi-line command is “> “. Let us change this default behavior to display “continue->” by using PS2 environment variable as shown below.

ramesh@dev-db ~> myisamchk --silent --force --fast -- update-state \

>  --key_buffer_size=512M  --sort_buffer_size=512M  \

>  --read_buffer_size=4M  --write_buffer_size=4M  \

>  /var/lib/mysql/bugs/*.MYI

[Note: This uses the default ">" for continuation prompt]

ramesh@dev-db  ~>  export  PS2="continue->  "

ramesh@dev-db ~> myisamchk --silent --force --fast -- update-state \

continue-> --key_buffer_size=512M -- sort_buffer_size=512M \

continue->  --read_buffer_size=4M  --write_buffer_size=4M

\

continue->  /var/lib/mysql/bugs/*.MYI

[Note:  This  uses  the  modified  "continue->  "  for

continuation  prompt]

I found it very helpful and easy to read, when I break my long commands into multiple lines using \. I have also seen others who don’t like to break-up long commands.