Rename "can_display_colour" and "can_display_utf8" to "terminal_supports_colour" and "terminal_supports_utf8" to make it clearer that these are not operator-supplied option settings, they are derived from terminal capabilities (colour) and the environment (UTF-8).

src/include/pv-internal.h

@@ -197,8 +197,8 @@ struct pvstate_s {
 		bool no_splice;                  /* never use splice() */
 		bool discard_input;              /* write nothing to stdout */
 		bool show_stats;		 /* show statistics on exit */
-		bool can_display_utf8;		 /* whether UTF-8 output is permitted */
-		bool can_display_colour;	 /* whether the terminal supports colour */
+		bool terminal_supports_utf8;	 /* whether the terminal supports UTF-8 */
+		bool terminal_supports_colour;	 /* whether the terminal supports colour */
 		bool checked_colour_support;	 /* whether we have checked colour support yet */
 		bool width_set_manually;	 /* width was set manually, not detected */
 		bool height_set_manually;	 /* height was set manually, not detected */

src/include/pv.h

@@ -237,7 +237,7 @@ extern void pv_state_watch_pid_set(pvstate_t, pid_t);
 extern void pv_state_watch_fd_set(pvstate_t, int);
 extern void pv_state_output_set(pvstate_t, int, const char *);
 extern void pv_state_average_rate_window_set(pvstate_t, unsigned int);
-extern void pv_state_set_can_display_utf8(pvstate_t, bool);
+extern void pv_state_set_terminal_supports_utf8(pvstate_t, bool);
 
 extern void pv_state_inputfiles(pvstate_t, unsigned int, const char **);