On Wed, Jan 30, 2002 at 12:20:02PM +0200, Matan wrote:
> On Wed, 30 Jan 2002, Johannes Zellner wrote:
> >
> > if I'm running svgalib in screen (a terminal mutliplexer, see
> > http://www.gnu.org/software/screen/screen.html) and try to
> > use svgalib I get the following message:
> >
> > You must be the owner of the current console to use svgalib.
> > Not running in a graphics capable console,
> > and unable to find one.
> >
> > I'm using svgalib 1.9.12.
> > What's the problem?
>
> I think using screen is the same (as far as svgalib is concerned) as
> running telnet localhost, so svgalib does not know the program is
> actually running on the local console.
> I am not sure it's a good idea to run an svgalib program from a screen
> session - when you try to move to another window, svgalib won't catch
> that (as it catches vc switches), so you will now run a program that
> thinks it's in text mode, but the video card is actually in graphics
> mode.
>
> I guess that the only real solution is to add support for screen, the
> same as there is support for linux virtual consoles.
ok. attached is a small patch which works on screen.
--
Johannes
*** ./vga_console.c.orig Wed Jan 30 11:47:28 2002
--- ./vga_console.c Wed Jan 30 12:17:03 2002
***************
*** 95,105 ****
--- 95,115 ----
{
struct stat sbuf;
char fname[30];
+ char* sty;
#ifdef ROOT_VC_SHORTCUT
if (!getuid())
return 1; /* root can do it always */
#endif
+ /* support for running svgalib from 'screen' */
+ if ((sty = getenv("STY"))) {
+ /* screen exports something like "STY=568.tty1.orbital"
+ * so check if sty contains the ttyX string */
+ sprintf(fname, "tty%d", vc);
+ if (strstr(sty, fname)) {
+ return 1;
+ }
+ }
sprintf(fname, "/dev/tty%d", vc);
if ((stat(fname, &sbuf) >= 0) && (getuid() == sbuf.st_uid)) {
return 1;
