Hi DOSEMU and FreDOS developers, FreeDOS 'more' command (tried both 4.2 and 4.3 versions) isn't working correctly under DOSEMU when used in screen resolutions other than 80 columns x 25 rows. From its code (function GetScreenSize() in more.c) it seems as more compute no. of screen rows from BIOS data area, from 40h:4Ah (Columns on screen) and 40h:4Ch (Video page size) values, using formula: ROWS=Video page size / Columns on screen / 2
which in this case give bad results, as Video page sizes are multiples of 4k (number of columns is OK). Here is what Video page size values are returned in certain text modes: 80x25 - 40:4C=0x1000=4096, more has 25 rows. 80x25x2=4000=0xFA0 80x43 - 40:4C=0x2000=8192, more has 51 rows. 80x43x2=6880=0x1AE0 80x50 - 40:4C=0x2000=8192, more has 51 rows. 80x50x2=8000=0x1F40 80x60 - 40:4C=0x3000=12288, more has 76 rows. 80x60x2=9600=0x2580 132x25 - 40:4C=0x2000=8192, more has 31 rows. 132x25x2=6600=0x19C8 132x43 - 40:4C=0x3000=12288, more has 46 rows. 132x43x2=11352=0x2C58 132x60 - 40:4C=0x4000=16384, more has 62 rows. 132x60x2=15840=0x3DE0 >From some informations on net (e.g. here: http://marc.info/?l=freedos-dev&m=106291977718089&w=2 ) it seems as video page size isn't reliable/suitable for no. of rows on screen computing - but I'm not sure, as this may be DOSEMU bug as well. I want to report a bug, but what? DOSEMU, or 'more' command? Note that 'mode con' properly report no. of cols/rows, and when I in 'more' use 40h:84h (Rows on screen minus one) value (i.e. patch as --- more.c.old 2007-09-23 13:04:00.000000000 +0200 +++ more.c 2014-05-04 00:26:47.948102176 +0200 @@ -84,15 +84,15 @@ void GetScreenSize(void) { unsigned char bios_screencols = *(unsigned char far *)MK_FP(0x40,0x4a); - unsigned short bios_screensize = *(unsigned short far *)MK_FP(0x40,0x4c); - + unsigned char bios_screenrows = *(unsigned char far *)MK_FP(0x40,0x84); + if (bios_screencols != 0) { COLS = bios_screencols; - if (bios_screensize != 0) + if (bios_screenrows != 0) { - LINES= bios_screensize/bios_screencols/2; + LINES= bios_screenrows + 1; } /* printf("BIOS screen size = %u/%u\n",LINES,COLS); */ then more works OK in all modes. Thanks, Franta Hanzlik ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available. Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Dosemu-devel mailing list Dosemu-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dosemu-devel
