less emulate a TTY to preserve piped color output
Solution 1:
It's not less that needs to change. The output of your other programs is being redirected to a pipe. Those programs detect that their output is not being sent to a tty and they disable their coloring. You're stuck with having to do something special with the source programs to color their output even when redirected to a pipe.
I think I have a solution for the programs that do not support a --color=always option. The unbuffer command creates a pty and sends the output of its argument program to that pty, therefore the argument program thinks its output is going to a tty and colors it.
I tried the following as an experiment and it worked. I couldn't think of any programs that color their output by default.
$ unbuffer ls --color=auto | cat
Also, don't you have to use the -r option with less to get it to display color? I also tried this:
$ unbuffer ls --color=auto | less -r
Solution 2:
on FreeBSD you can:
env CLICOLOR_FORCE=yes ls -l | less -R
or you can set/override options (csh/tcsh):
alias less less -R
setenv CLICOLOR_FORCE yes
setenv LS_COLORS "no=00:fi=00:di=01;36:ln=01;37;44:pi=40;33:so=01;35"
setenv LS_COLORS "$LS_COLORS":"bd=40;33;01:cd=40;33;01:or=40;31;01"
setenv LS_COLORS "$LS_COLORS":"ex=01;32;40:*.tar=01;31:*.tgz=01;31"
setenv LS_COLORS "$LS_COLORS":"*.arj=01;31:*.taz=01;31:*.lzh=01;31"
setenv LS_COLORS "$LS_COLORS":"*.zip=01;31:*.z=01;31:*.Z=01;31"
setenv LS_COLORS "$LS_COLORS":"*.gz=01;31:*.deb=01;31:*.jpg=01;35"
setenv LS_COLORS "$LS_COLORS":"*.gif=01;35:*.bmp=01;35:*.ppm=01;35"
setenv LS_COLORS "$LS_COLORS":"*.tga=01;35:*.xbm=01;35:*.xpm=01;35"
setenv LS_COLORS "$LS_COLORS":"*.tif=01;35:*.mpg=01;37:*.avi=01;37"
setenv LS_COLORS "$LS_COLORS":"*.gl=01;37:*.dl=01;37:*.tex=01;35"
setenv LS_COLORS "$LS_COLORS":"*.ps=01;35"
setenv LS_COLORS "$LS_COLORS":"*.php=01;33"
setenv LS_COLORS "$LS_COLORS":"*.sh=00;31"
setenv LS_COLORS "$LS_COLORS":"*.txt=01;37:*.conf=01;37:*.config=01;37"
setenv LSCOLORS GxExcxdxCxegedabagacad
in ~/.cshrc