I'm currently on vacation with very limited ability to test, but I do approve of this way.
/Alexander On June 17, 2018 5:00:17 PM GMT+02:00, "Todd C. Miller" <[email protected]> wrote: >On Sat, 16 Jun 2018 16:16:57 -0600, "Todd C. Miller" wrote: > >> On Sat, 16 Jun 2018 14:50:40 +0200, Mark Kettenis wrote: >> >> > To be honest, I find the whole idea of invoking an external program >to >> > clear the screen insane. >> >> Linking with curses doesn't increase the size a huge amount since >> we just need to query terminfo. >> >> text data bss dec hex >> 529120 12584 57024 598728 922c8 /bin/ksh >> 595671 21904 57024 674599 a4b27 ./obj/ksh > >Slightly simpler, we can use the clear_screen macro instead of looking >it up with tigetstr(). > >text data bss dec hex >529120 12584 57024 598728 922c8 /bin/ksh >594844 21888 57024 673756 a47dc ./obj/ksh > > - todd > >Index: Makefile >=================================================================== >RCS file: /cvs/src/bin/ksh/Makefile,v >retrieving revision 1.38 >diff -u -p -u -r1.38 Makefile >--- Makefile 6 Jan 2018 16:28:58 -0000 1.38 >+++ Makefile 16 Jun 2018 22:00:32 -0000 >@@ -1,6 +1,9 @@ > # $OpenBSD: Makefile,v 1.38 2018/01/06 16:28:58 millert Exp $ > > PROG= ksh >+DPADD+= ${LIBCURSES} >+LDADD+= -lcurses >+ >SRCS= alloc.c c_ksh.c c_sh.c c_test.c c_ulimit.c edit.c emacs.c eval.c >\ > exec.c expr.c history.c io.c jobs.c lex.c mail.c main.c \ > misc.c path.c shf.c syn.c table.c trap.c tree.c tty.c var.c \ >Index: edit.c >=================================================================== >RCS file: /cvs/src/bin/ksh/edit.c,v >retrieving revision 1.65 >diff -u -p -u -r1.65 edit.c >--- edit.c 9 Apr 2018 17:53:36 -0000 1.65 >+++ edit.c 16 Jun 2018 22:09:17 -0000 >@@ -138,10 +138,10 @@ x_flush(void) > shf_flush(shl_out); > } > >-void >+int > x_putc(int c) > { >- shf_putc(c, shl_out); >+ return shf_putc(c, shl_out); > } > > void >Index: edit.h >=================================================================== >RCS file: /cvs/src/bin/ksh/edit.h,v >retrieving revision 1.11 >diff -u -p -u -r1.11 edit.h >--- edit.h 26 Jan 2016 17:39:31 -0000 1.11 >+++ edit.h 16 Jun 2018 22:09:27 -0000 >@@ -37,7 +37,7 @@ extern X_chars edchars; > /* edit.c */ > int x_getc(void); > void x_flush(void); >-void x_putc(int); >+int x_putc(int); > void x_puts(const char *); > bool x_mode(bool); > int promptlen(const char *, const char **); >Index: emacs.c >=================================================================== >RCS file: /cvs/src/bin/ksh/emacs.c,v >retrieving revision 1.84 >diff -u -p -u -r1.84 emacs.c >--- emacs.c 16 Jan 2018 17:17:18 -0000 1.84 >+++ emacs.c 17 Jun 2018 13:58:36 -0000 >@@ -21,6 +21,10 @@ > #include <stdio.h> > #include <stdlib.h> > #include <string.h> >+#ifndef SMALL >+# include <term.h> >+# include <curses.h> >+#endif > > #include "sh.h" > #include "edit.h" >@@ -28,6 +32,7 @@ > static Area aedit; > #define AEDIT &aedit /* area for kill ring and macro defns */ > >+#undef CTRL > #define CTRL(x) ((x) == '?' ? 0x7F : (x) & 0x1F) /* > ASCII */ > #define UNCTRL(x) ((x) == 0x7F ? '?' : (x) | 0x40) /* > ASCII */ > >@@ -146,6 +151,7 @@ static int isu8cont(unsigned char); > /* proto's for keybindings */ > static int x_abort(int); > static int x_beg_hist(int); >+static int x_clear_screen(int); > static int x_comp_comm(int); > static int x_comp_file(int); > static int x_complete(int); >@@ -202,6 +208,7 @@ static int x_debug_info(int); > static const struct x_ftab x_ftab[] = { > { x_abort, "abort", 0 }, > { x_beg_hist, "beginning-of-history", 0 }, >+ { x_clear_screen, "clear-screen", 0 }, > { x_comp_comm, "complete-command", 0 }, > { x_comp_file, "complete-file", 0 }, > { x_complete, "complete", 0 }, >@@ -1004,12 +1011,19 @@ x_draw_line(int c) > { > x_redraw(-1); > return KSTD; >+} > >+static int >+x_clear_screen(int c) >+{ >+ x_redraw(-2); >+ return KSTD; > } > >-/* Redraw (part of) the line. If limit is < 0, the everything is >redrawn >- * on a NEW line, otherwise limit is the screen column up to which >needs >- * redrawing. >+/* Redraw (part of) the line. >+ * A non-negative limit is the screen column up to which needs >+ * redrawing. A limit of -1 redraws on a new line, while a limit >+ * of -2 (attempts to) clear the screen. > */ > static void > x_redraw(int limit) >@@ -1018,9 +1032,25 @@ x_redraw(int limit) > char *cp; > > x_adj_ok = 0; >- if (limit == -1) >+ if (limit == -2) { >+ int cleared = 0; >+#ifndef SMALL >+ char *term = str_val(global("TERM")); >+ if (term && *term) { >+ int errret; >+ if (setupterm(term, 1, &errret) != ERR && >+ clear_screen != NULL && *clear_screen != '\0') { >+ if (tputs(clear_screen, 1, x_putc) != ERR) >+ cleared = 1; >+ } >+ } >+#endif >+ if (!cleared) >+ x_e_putc('\n'); >+ } >+ else if (limit == -1) > x_e_putc('\n'); >- else >+ else if (limit >= 0) > x_e_putc('\r'); > x_flush(); > if (xbp == xbuf) { >Index: ksh.1 >=================================================================== >RCS file: /cvs/src/bin/ksh/ksh.1,v >retrieving revision 1.200 >diff -u -p -u -r1.200 ksh.1 >--- ksh.1 30 May 2018 21:20:52 -0000 1.200 >+++ ksh.1 16 Jun 2018 12:29:34 -0000 >@@ -4690,6 +4690,10 @@ Moves the cursor to the beginning of the > Uppercase the first character in the next > .Ar n > words, leaving the cursor past the end of the last word. >+.It clear-screen: >+Attempts to clears the screen by invoking >+.Xr clear 1 >+and redraws the prompt and current input line. > .It comment: ^[# >If the current line does not begin with a comment character, one is >added at >the beginning of the line and the line is entered (as if return had >been
