The actual colors to be used are configured using the environment variable
   LT_COLORS
   (note plural).  The value is a colon-separated list of
   
   pairs.  The keys specify what the color is to be used for.  The values are
   SGR (Select Graphic Rendition) specifications, which are interpreted by the
   terminal.
  key=value
The following keys are currently in use:
errorused to highlight the text “error” in error messages
warningused to highlight the text “warning” in warning messages
locusused to highlight location information (e.g., program name and file name) in messages
   The default value is error=01;31:warning=01;35:locus=01
   (01;31 = bold red, 01;35 = bold
   magenta, 01 = bold default color).
  
This color specification format is also used by other software packages such as GCC, GNU coreutils, and GNU grep.