Modernize the tty/line prompt.

tcshrc.prompt.final

@@ -7,6 +7,14 @@ if( $?CSHENV_DEBUG ) then
 endif
 
 # Recompute cached sgr codes from any configuration updates
+if( ! $?curr_line_color ) then
+    set curr_line_color=impossible
+endif
+if( "${curr_line_color}" != "${line_color}" ) then
+    set curr_line_color="${line_color}"
+    set line_color_seq="%{[`__build_sgr_code no-csi reset ${curr_line_color}`m%}"
+endif
+
 if( ! $?curr_path_color ) then
     set curr_path_color=impossible
 endif
@@ -232,7 +240,7 @@ if( ! $?CSHENV_DISABLE_PROMPT_SIGIL ) then
     set prompt_reference_view="${prompt_reference}"
 endif
 if( ! $?CSHENV_DISABLE_PROMPT_TTY ) then
-    set line_prompt_view="${line_prompt}"
+    set line_prompt_view="${line_color_seq}${line_prompt}"
     set line_spacer_view="%{${text_color_seq}%}\- "
 endif
 if( ! $?CSHENV_DISABLE_PROMPT_NESTING ) then