basic prompt:          PROMPT_COMMAND="echo -ne \"\033]0;${USER}@${HOSTNAME} `tty` ${PWD/$HOME/~}\007\""


test:         (( history | tail -2 | head -1 | grep \"vim\|less\" ))           doesn't work because of \" for grep...


and the final thing that needs to be modified till it works :D :

PROMPT_COMMAND="(( history | tail -2 | head -1 | grep \"vim\|less\" )) || 'echo -ne \"\033]0;${USER}@${HOSTNAME} `tty` ${PWD/$HOME/~}\007\"' && 'echo -ne \"\033]0;${USER}@${HOSTNAME} `tty` $_ {PWD/$HOME/~}\007\"'"