I have a log file captured by tclsh which captures all the backspace characters (ctrl-H, shows up as "^H") and color-setting sequences (eg. ^[[32m .... ^[[0m ). What is an efficient way to remove them? ^[...m This one is easy since, I can just do "sed -i /^[.*m//g" to remove them ^H Right now I have "sed -i s/.^H//", which "applies" a backspace, but I have to keep looping this until there are no more backspaces. while [ logfile == `grep -l ^H logfile` ]; do sed -i s/.^H// logfile ; done; "sed -i s/.^H//g" doesn't work because it would match consecutive backspaces. This process takes 11 mins for my log file with ~6k lines, which is too long. Any better ways to remove the backspace?