Shareware Overload Trio 2

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Text File | 1995-02-15 | 59KB | 1,255 lines

╒═══════════════════════════════════════════╕ │ xDISK │ │ Release 3.60.0 │ │ │ │ (C) Copyright 1989-1993 FM de Monasterio │ │ All Rights Reserved │ │ Licensed Material │ ╘═══════════════════════════════════════════╛ CONTENTS 1. SUMMARY 2. REGISTRATION 3. GENERAL INFORMATION 4. INSTALLATION & USAGE a. Installing the driver via CONFIG.SYS b. Installing from the DOS command line c. Modifying the driver after installation Command-line switches Command-line comments d. Status/Usage/Help panels 5. BASIC TECHNICAL INFORMATION a. DOS Errorlevels b. Disk internals c. RAM-Disk identification & DOS version d. Self-installation in upper memory e. xDISK communication interface 6. COPYRIGHT & LICENSE U.S. Government information Upgrades Limitations Technical support 1. SUMMARY ----------- xDISK is a versatile EMS-based, RAM-disk whose size can be modified without having to reboot the machine. Sector size, cluster size, and root directory size can be changed as well. The disk can provide visual and audio clues of its activity. xDISK generates the disks in expanded memory conforming to the Lotus/Intel/ Microsoft (LIM) specification 4.0 (EMS). xDISK can be collapsed to free its EMS for other uses, and can be expanded to use all of the available EMS, or any intermediate size multiple of 16 kilobytes (KB). xDISK does not use the EMS page frame, thus avoiding the need to dedicate 64 KB of memory for this frame. Two kinds of on-the-fly resizable xDISKs can be created: "Inelastic," which maximizes disk space, but whose data contents are not preserved if the disk is resized; and "elastic," which permits data-preserving and non-preserving disk resizing. Security features include: RAM-disk write protecting and format protecting, locking/unlocking DOS access to the disk, and the enforcing of user-defined password checks before the implementation of any command to the disk. Loading features include selfinstallation of the xDISK device driver in the upper memory area, with or without MS-DOS 5+, if an extended memory manager supporting the XMS 2+ is present, and the capability of loading this driver from the DOS command line (MS-DOS and PC-DOS versions 3.0 through 6.0). Minimum xDISK requirements are MS-DOS version 3.0 or later (or a compatible operating system), expanded memory conforming to the LIM EMS 4.0, and 1,500 bytes of conventional (or upper memory) per drive to be installed. xDISK is available in 086, 286, 386, and 486 microprocessor-type optimized versions. 2. REGISTRATION ---------------- This software is user-supported; the present release, although lacking the options marked by asterisks, is a fully usable program. You may test this release for (in)compatibilities with your system, but after the testing is completed you are requested to order a registered copy of the full release of the software from the address at the end of this documentation. See the final part of this documentation for information on the Licensing, Distribution, Warranty, and Limitation of Remedies of the software. -------------------------------------------------------------------- XDISK.REG contains a form needed to register or upgrade the software -------------------------------------------------------------------- If you would rather use this unregistered copy, consider making a donation to the Children's Hospital of Washington DC, for indigent children in need of medical care. Every year in the USA, infant mortality claims the lives of tens of thousands of children before their first year of life, and most of them come from families below poverty level... Please send to the same address a check payable to the "PATIENT CARE FUND, CHILDREN'S HOSPITAL" on the obverse, and marked "For Deposit Only" on the reverse. Donations will be sent to Children's Hospital. Please identify the program for which you are making the donation. 3. GENERAL INFORMATION ----------------------- xDISK is a virtual-device driver system to generate (and modify) RAM-disks in expanded memory conforming to LIM specification version 4 or higher. The disk parameters can be modified without having to reboot the machine. A a data-safe resizing can be obtained with some command switches. Data-safe resizing is available if the RAM-disk has been installed as an "elastic" unit (the default condition). xDISK can also be installed as an "inelastic" unit, which can be resized on-the-fly as well, but whose resizing destroys the disk contents; "inelastic" disks maximize the usage of EMS disk space. This system consists of two programs: (1) XDISK.SYS, a block device driver to be installed via CONFIG.SYS, after an EMS manager has been installed, and (2) XDISK.EXE, a utility providing an interface with the driver via DOS to permit changing of one or more parameters of the specified RAM-disk. Warning ----------------------------------------------------------------- Due to an error in the LH (LOADHIGH) command of MS-DOS and PC-DOS 5.00 and MS-DOS 6.00, XDISK.EXE does not select the correct drive if loaded via this command in either upper or lower memory. (The LH command is not needed for the execution of the drive interface utility.) ----------------------------------------------------------------- The XDISK.SYS and XDISK.EXE files of a given version are matched and will not work with those of other xDISK versions. The minimum requirements are an EMS- 4.0 manager, and MS-DOS version 3 or later. Some xDISK options require MS-DOS 3.1+ version or later (see below). Since xDISK does not require an EMS page frame (i.e., a large region of upper memory where the EMS 'pages' are normally posted), 64 KB can be recovered for upper-memory use if frame-dependent EMS utilities are not used. EMS services without a page frame are supported by most 386-specific memory managers, such EMM386.EXE (use switch FRAME=NONE in MS-DOS 5 and 6 version), 386MAX.SYS (use switch NOFRAME), QEMM386.SYS (use switches FR=NONE FEMS), etc. xDISK RAM-disks are compatible with the CHKDSK utility of DOS as well as with other programs that sometimes encounter difficulties with other resizable RAM disks. Starting with xDISK version 3.32, the boot sector of the disk complies fully with the MS-DOS version 5 and 6 format. CPU versions The program is written in assembly language; each version consists of four processor-type releases (086, 268, 386 and 486) in which the code has been optimized for the CPU types of the Intel iAPX processor family (x86). This is needed because such processors differ markedly in instruction execution time. Incorporation of a memory cache in some x86 processors also affects this time by influencing the speed of both instruction fetching and memory access. The 486 release should be used with 586 CPU (Pentium) machines. In addition to standard (086) assembly language instructions, the 286, 386 and 486 releases of the program also use 286-, 386- or 486-specific opcode instructions in 'real' mode (which is the native mode for 086 processors). The type and degree of code optimization vary with the CPU type, and yield usually small variations of the size of the resident code. These releases can be used in machines having the corresponding or higher CPU type. 4. INSTALLATION & USAGE ------------------------ The utility INSTALL.EXE, enclosed with the program files, may be used to copy these files to a user-defined drive and directory, and--if so desired--to add a command to the file CONFIG.SYS which will install the driver XDISK.SYS upon rebooting, and to add the user-defined directory to the PATH statement in the AUTOEXEC.BAT file. The following sections describe the manual installation of the xDISK driver. A. Installing via CONFIG.SYS XDISK.SYS may be installed via the CONFIG.SYS file on the boot disk after the LIM-3+ EMS manager has been installed. The filename of the EMS driver varies with the manufacturer, but its code must include the string 'EMMXXXX0,' whose presence can be verified with a file-browsing utility. The following command must be included in the file CONFIG.SYS: DEVICE=[path]XDISK.SYS [?n] [/DB/DR/DS/KB/LH/PK/VD/VM] [;comment] where <path>, if given, is the path specification (including drive) for XDISK .SYS; if <path> is not specified, the driver file is assumed to be located in the root directory of the booting drive. Comments preceded by a semicolon in the DEVICE= line specification, which may be useful in annotating CONFIG.SYS commands, are ignored during installation. A description of the switches (/DB, /DR, etc) is provided below. The default value for switch /DB, /DR, or /DS is used if the switch (or its corresponding parameter) is not specified. The SIZE parameter needs not be specified if using the DEVICEHIGH (MS-DOS 5+) or the HIDEVICE (DR-DOS 6) command to install the driver in the upper memory. Installation avoidance In registered copies of xDISK, driver installation can be avoided by pressing the <Esc> key before the installation banner is displayed. Pressing this key interrupts the installation, and the user is prompted as to whether the drive is to be installed: xDISK: Continue loading RAM-disk as drive X:? [Yn] Press <Y> or <Enter> to continue or <N> to cancel. Avoiding the installation produces no memory penalty under DOS version 3.30 or higher but uses some 256 bytes of conventional memory in earlier DOS versions. B. Installing from the DOS command line Alternatively, the driver may also be loaded from the command line at the DOS prompt (that is, after the system has been booted and configured via the file CONFIG.SYS) by means of the associated utility XDISK.EXE. Command-line is not yet imlpemented under DR-DOS version 5+. Assuming XDISK.EXE is in the DOS path, the following command must be used for the command-line loading of the driver: XDISK /LX=[path]XDISK.SYS [/switches] or XDISK /LX:[path]XDISK.SYS [/switches] where <path>, if given, is the directory path specification (including drive) for the XDISK.SYS file; if <path> is not specified, the file is assumed to be located in the current directory. The use of a colon or equal sign after /LX is mandatory. (See below for the description of the command switches.) xDISK drives loaded from the DOS prompt can be uninstalled via XDISK.EXE (see switch /UX below). The maximum number of drives allowed by MS-DOS, including floopy, hard, and RAM-disks, is 26 (A: through Z:). C. Modifying the xDISK driver After the xDISK driver has been installed, XDISK.EXE can be used to interface with the driver. This utility allows for the modification of disk parameters from the DOS command line: XDISK [?] [d: [/switches]] [;comments] ? If xDISK is executed with <?> as the only argument (notice the absence of a preceding backslash), the program searches all block device drivers for the xDISK driver signature, and displays a list of the installed drivers. d This is the drive designator letter, followed by <:>, that identifies the xDISK drive. The specification of a non-xDISK drive or of a non-existing drive generates separate error messages. Defaults: Null drive, no colon, or x=<ASCII code 21-40> = Current drive unit letter. The two other components of the command line are discussed below: SWITCHES -------- Switches are optional commands, passed to the driver to modify its operation, which are added to the command line invoking the xDISK driver (at the time of installation) or its XDISK.EXE interface utility. The switches are not case sensitive, but must be preceded by a backslash [/]. If xDISK is invoked without any switch (or when the switches are not preceded by slashes, and thus are ignored), the status of the xDISK drive is displayed at the DOS command line. The contents of the RAM-disk are destroyed by the switches /DB, /DR, /DS, /DC and /DE, which reformat the disk. The contents are preserved by the switches /DX+ and /DX-, which resize the disk without reformatting. Only the following switches are recognized when loading the driver: /DB, /DR, /DS, /DU, /KB, /LH, /PK, /VD, and /VM All switches are recognized after installation of the driver, except for /DU, /KB, /LH, /PK, and /VM. ------------------------------------------------------------------------ (*) Asterisks mark options available in the registered program copy only ------------------------------------------------------------------------ SWITCH ? 1. XDISK.SYS: If <?[n]> immediately follows the blank space terminating the driver name in the DEVICE= line specification, the user is prompted as to whether the corresponding RAM-disk is to be installed. If <n> is missing or is not a digit between 1 and 9, such prompt defaults to a YES answer in 5 seconds. The prompt time-out value is provided by <n> if between the range 1 to 9; the driver is forced to wait for an answer if n=0. 2. XDISK.EXE: This switch displays the Status/Usage/Help panels, which are described in more detail in the section below. If a VGA or EGA is the active adapter, the program saves the contents of the palette registers prior to changing the video attributes for its various displays. Preceded by a valid xDISK drive unit letter, <?> or </?> display the disk status at the DOS prompt (/?) or at the xDISK Usage/Help panel (?). In the absence of a drive designator, <?> displays the list of the loaded xDISK RAM-disks, and </?> displays either the status of the default drive (if an xDISK one) or the list of installed disks (if the default drive is not an xDISK drive). See section Status/Usage/Help Panels below. * SWITCH CS[n] Selects cluster size, i.e., DOS allocation units, where <n> can be 1, 2, 4, 8, 16, or 32 sectors/cluster; the final size may be adjusted by xDISK to a higher value, especially if dealing with a large disk. The smaller the size the lesser the chance to degrade the compactness of the packing of files in the disk (which affects switch /DX; see below). Defaults: /CS = /CS1. * SWITCH DA[±] Selects whether changes in the disk parameters are implemented via calls to DOS (/DA+) or directly to the driver (/DA-). If an on-the-fly, data- compression utility is being used to increase disk capacity, which would normally take over DOS calls to xDISK, do not resize the disk via direct calls to the driver (/DA-) since this will damage such a utility. Defaults: /DA = /DA+. SWITCH DB[n][!] Selects disk size, in which <n> is between 16 and 32768 KB in steps of 16 KB. If <n> is not a 16-KB multiple, the size is increased to the nearest larger multiple available. The largest RAM-disk size supported is 32 MB. Unless switch /ND or /NQ is selected as well, disk resizing by switch /DB requires confirmation by the user, since the disk is reformatted, and its contents are thus destroyed. Switch /DB[n] installs an "elastic" disk that, under many conditions, can expand or shrink via switch /DX± (see below) preserving the contents. In contrast, switch /DB[n]! installs an "inelastic" disk that allows maximal utilization of the EMS but disables data-safe expansion or shrinkage; use /DB[n]! if loading a RAM-disk that will not need resizing. Defaults: In CONFIG.SYS, null switch or null <n> = /DB64. In the command line of DOS, /DB = /DB64; null switch is ignored. * SWITCH DC Switch /DC collapses the RAM-disk to a size of 0 KB and releases all the EMS pages previosuly allocated to the disk. Unless switch /ND or /NQ is also selected, disk collapse requires user confirmation; switch /DC does not change the existing /DR and /DS values. If disk collapse has occurred for, say, disk J, DOS-mediated requests to the drive, e.g. <CHKDSK J:> or <DIR J:>, will trigger the folowing error message from MS-DOS 5+: Invalid disk change reading drive J Please insert volume xDISK∙360 serial 3600-0010 Abort, Retry, Fail? The serial number specifies the xDISK version (3.60.0) and the disk unit number (A=1, B=2, C=3... J=10) in a binary-packed decimal number format. Respond to the "Abort, Retry, Fail?" question by pressing the <A> key to return to the DOS prompt. This message is a remainder that the disk does exist, but it is collapsed. Such a disk can only be restored via switch /DB or /DE since reformatting is needed; the data-preserving switch /DX+ is not accepted if the disk is collapsed. Do not change drive to a collapsed RAM-disk as DOS will repeat the above prompt until key <F> is pressed. Disks failed by DOS generate different error messages to CHKDSK. A valid drive status is restored once the RAM disk is expanded via switch /DB or /DE. See switch /TL for invalidating and revalidating disk access. No defaults. * SWITCH DE[!] Expands disk size to the maximum available EMS. The maximum number root entries is changed to 512, unless switch /DR[n] is specified afterwards. Unless switch /ND or /NQ is also specified, this expansion requires user confirmation. Switch /DE loads an "elastic" disk which can expand or shrink via switch /DX± (see below), while preserving its contents during such resizing. In contrast, switch /DE! loads an "inelastic" disk whose contents cannot be preserved during resizing, but allows maximal EMS utilization. Use /DE! to create a RAM-disk that will not need resizing. No defaults. SWITCH DR[n] Number of root directory entries (files and subdirectories) where <n> is between 4 and 512. (The final number of root entries may be adjusted by xDISK to a higher or lower value, especially when loading a small disk.) Unless switch /ND or /NQ is also selected, this resizing change requires confirmation by the user. Each root directory entry uses 32 bytes from the allocated disk size. Warning ----------------------------------------------------------- If there is not a sufficient number of entries, commands to write to the disk trigger a critical error message of 'File Creation Error.' To decrease such a possibility, expanding the disk to the maximum EMS size via switch /DE changes the root directory entries to 512. If less entries are needed, follow switch /DE with /DRn, where n < 512. ----------------------------------------------------------- Defaults: In CONFIG.SYS, null switch or null <n> = /DR64. In the command line of DOS, /DR = /DR64; null switch is ignored. SWITCH DS[n] Sector size, where <n> is 128, 256 or 512 bytes. The standard DOS sector is 512 bytes; use a smaller size when storing small files. Unless switch /ND or /NQ is also selected, the resizing change requires confirmation by the user. Defaults: In CONFIG.SYS, null switch or null <n> = /DS512. In the command line of DOS, /DS = /DS512; null switch is ignored. * SWITCH DX[±][n] Permits the limited shrinkage [-] and expansion [+] of the RAM-disk while preserving the integrity of its contents. Resizing is NOT implemented if the resulting drive parameters would threaten the disk contents (see Disk Internals below). Switch /DX- shrinks the free space of the disk to zero or to less than 16 KB. Alternatively, /DX-n shrinks the disk by <n> KB or the nearest 16-KB multiple. Shrinkage is not implemented if free space is less than 16 KB, as this would not free an EMS page (16 KB each). The data-safe shrinkage is available only under MS-DOS 3.10 or later version. Shrinking an empty disk yields a minimum size of 16 KB or more (depending on the other drive parameters), i.e., /DX- does not collapse the disk. Warning -------------------------------------------------------------- Switch /DX- uses an undocumented function supported in version 3.1 to 6.0 of MS-DOS; this function is also supported in other OEM releases of MS-DOS, such as PC-DOS, COMPAQ DOS, etc. There is no assurance, however, that such a function is supported in systems other than MS-DOS, or that it will remain available in future MS-DOS versions or revisions. -------------------------------------------------------------- The amount of shrinkage is computed from the value, maintained by MS-DOS, of the first cluster from which it starts the search for free space prior disk write operations (such a value is displayed on the Status panel, see Status/Usage/Help Panels below). DOS normally uses all of the previously unused free space before reusing freed space. Contents must be compacted (i.e. there should be no free gaps between used clusters) for proper disk shrinkage. Switch /DX- compares the calculated kilobytes needed to resize the disk with the amount occupied by the data. If the former are smaller than the latter, free gaps are assumed (i.e. the free-space cluster value does not indicate the last cluster in use) and shrinkage is cancelled. Note ------------------------------------------------------------------- To compact an "elastic" disk, use only a defragmenting utility that provides a full optimization, i.e., it does not leave free clusters interspersed among used clusters, such as the DEFRAG.EXE utility of MS-DOS 6. (Do not use a defragmenting utility that places a hidden data file in the last disk cluster, as this may interfere with disk shrinkage.) ------------------------------------------------------------------- Switch /DX+ expands total disk size to twice its formatted size, provided that the resulting drive parameters do not threaten the integrity of disk contents. Alternatively, switch /DX+n expands the disk by <n> KB, or the nearest higher 16-KB multiple. A disk shrunk via /DX- can be restored to its original (or a larger) size via switch /DX+ or /DX+n, and vice versa. A RAM-disk created with switch /DE! or /DB[n]! (fixed size) cannot be resized with switch /DX±. Defaults: /DX = /DX+. SWITCH DUd Assigns a tentative drive unit code to the disk to be installed, in which the unit code <d> can be a letter between "A" and "Z." Normally, DOS 3+, which is required to install xDISK, assigns such an unit code to the disk at the time of installation, overwritting any user-assigned code. Switch /DU is available for troubleshooting purposes and is ignored after driver installation. No defaults. * SWITCH KB Skips displaying the installation banner when loading the driver; switch /KB is ignored after installation. No defaults. * SWITCH LH[n] Selects installation of the xDISK driver in the upper memory area (UMA), i.e., between 640 KB and 1024 KB, which is below the 1-MB limit of 8086- based memory but above the 640-KB hardware barrier of DOS. Self-loading in upper memory requires an extended memory manager (XMM) supporting the services of XMS 2+, and a free upper memory block (UMB) of a little less than 2 KB. The XMM must support UMB functions. The UMB allocation is implemented by calls to DOS, if this allocation is managed by MS-DOS 5+ directly (i.e., command 'dos=umb' in CONFIG.SYS and the drivers HIMEM.SYS and 386EMM.EXE loaded), or via direct calls to the XMM, if MS-DOS 5+ does not control the UMB allocation. A low high-memory limit for the UMB may optionally be specified via <n>, a hexadecimal number between A000 (640 KB) and FFFF (1,024 KB), so as to select or avoid specific regions of upper memory. The self-loading into upper memory consumes 64 bytes of the conventional memory per installed device; a few additional bytes are taken by the XMM or MS-DOS during UMB allocation. Unlike the UMB loading mediated by some memory managers, xDISK self-loading only requires a free UMB of the size of the resident driver code (and not of the whole code of XDISK.SYS). Defaults: Lower-memory installation, if a XMS/DOS error is found during the UMB loading; high-memory installation below requested lower limit if UMBs are not available above this limit. Note ------------------------------------------------------------------- Due to the manner in which the DOS 5+ command 'DEVICEHIGH' modifies the upper memory chain (if this command and the command DOS=UMB are specified in CONFIG.SYS), self-loading into the upper memory is not possible if 'DEVICEHIGH' were used to install another device driver in a line preceding that of xDISK. (To install XDISK.SYS in a UMB, specify switch /LH in a 'DEVICE' line of CONFIG.SYS, and avoid this switch in a 'DEVICEHIGH' line.) Under MS-DOS 5+, xDISK can selfload into the upper memory area when 'DEVICEHIGH' is used in a command line subsequent to that of xDISK. ------------------------------------------------------------------- * SWITCH LX Loads XDISK.SYS from the DOS command line (i.e. after the system has been booted and the drivers installed via the CONFIG.SYS file). The full-path specification for XDISK.SYS must be given after switch /LX along with any switches to configure the xDISK driver, as shown above in Usage item 2.0. An equal sign or colon must separate /LX and the path specification with- out intervening spaces, as otherwise the loading will fail. Switch /LX does not require a drive specification. Previously installed xDISK disks should not be collapsed for the command- line loading to work properly, since the loading process rebuilds the DOS kernel. Command-line loading of the driver increases the resident size by slightly more than 1 KB. xDISK command-line loading is available under MS-DOS 3-6, IBM PC-DOS 3-6, COMPAQ DOS 3-4, and other OEM releases of MS-DOS. It is not yet available under DR-DOS version 5 and 6. Warning -------------------------------------------------------------- The system will crash if the memory allocated to the driver is released by means of a resident-removal utility! Command-line loaded drivers can be identified in memory maps via the string 'xDISK_<d:>,' where <d> is the drive letter for the disk. -------------------------------------------------------------- xDISK drives loaded from the command-line either in lower (LMB) or upper memory (UMB) can be unloaded from memory via switch /UX (see below). No defaults. * SWITCH ND Nulls the displaying of disk status, user confirmation request, and error messages; errors can still be detected within a batch file with the ERROR LEVEL command. Because the disk status display is generated by the driver via BIOS calls, this message cannot be redirected by DOS (switch /ND thus yields the same result as a redirection to the NUL device). The RAM-disk configuration parameters are preserved. No defaults. SWITCH NQ Quiet resizing. Avoids prompting for the user confirmation prior to disk resize operations that destroy all data on the RAM-disk. No defaults. * SWITCH PDx Defines passssword <x> to be checked before implementing any disk change, where <x> consists of 1-15 unshifted, alphanumeric characters (0-9, A-Z), which must be followed by a blank space. The password is useful in situations when more than one user has acces to the RAM-disk (e.g., a server) and, after copying the common-access files, the disk is made write- and format-protected. No defaults. * SWITCH PK Pauses driver installation after its banner has been displayed until any key is pressed; switch /PK is ignored after installation. No defaults. * SWITCH TL[±] Unlink (/TL-) or relink (/TL+) the drive to the chain of DOS drivers. The unlinking turns the driver off, invalidating its use by DOS. This may be useful for collapsed disks that cannot be unloaded from memory. Unlinked RAM-disks can be turned on by relinking them to the DOS chain. Defaults: /TL = /TL+. * SWITCH TP[±] Disables (/TP-) or enables (/TP+) password verfication before any changes to the RAM-disk are implemented; the password consists of 1-15 unshifted, alphanumeric characters followed by <Enter>. Pressing <Esc> or <Break> during password testing returns the user to the DOS command line. The typing of an incorrect character during the testing vitiates prior accepted (correct) characters, and the entire password has to be retyped. Note that warmbooting via <Ctrl-ALt-Del> is not suppressed during password testing; rebooting destroys the RAM-disk data. Defaults: /TP = /TP+. * SWITCH TPA[±] Provides control of the audio feedback during the password checking (see switch TP below) prior to the implementation of any change in the drive; /TPA+ enables a 55-ms beep each time an invalid character is entered and /TPA- disables this feedback. Defaults: /TPA = /TPA+. * SWITCH TPV[±] Provides control of the video feedback during the password checking (see switch TP below) prior to the implementation of any change in the drive; /TPV+ displays a <■> if a correct character is typed, and /TPV- disables this feedback. Defaults: /TPV = /TPV+. * SWITCH TR[±] Protect (/TR+) or unprotect (/TR-) the drive from resizing to prevent the inadvertent reformatting the disk. The protection status is indicated by the upper or lower case of the write-protection status (see switch TW) in the xDISK configuration message: RW/RO = resize protected, rw/ro = resize unprotected. Defaults: /TR = /TR+. * SWITCH TS[±] Provides control of audio feedback during DOS access to the specified RAM disk: Use /TS+ to enable a brief click whenever the driver receives a DOS request to read from or write to the disk, and /TS- to disable this audio feedback. The ON status is indicated by the icon <> in the configuration status messages. Defaults: /TS = /TS+. * SWITCH TV[±] Provides control of video feedback during DOS access to the specified RAM disk: Use /TV+ to flash the icon <> on the top-left corner of the screen each time the driver receives a request from DOS to read from or write to the disk, and /TV- to disable this video feedback. The ON and OFF status is signalled repectively by the icons <> and <∙> in the status messages. Switch /VD allows for the selection of the character and the attribute to be flashed by /TV+. Defaults: /TV = /TV+. * SWITCH TW[±] Use /W+ or /W- to write protect (Read-Only) or unprotect (Read-Write) the drive contents as in a floppy disk. Write-protect status does not permit RAM-disk resizing. The status is indicated by the icons <RO> and <RW> in the xDISK configuration status messages. Defaults: /TW = /TW+. * SWITCH UX Uninstalls from memory the specified xDISK disk (only command-line loaded drives can be uninstalled); the operating system will crash if this drive is not the last drive in the DOS chain or if the resident code is removed with a TSR-removal utility. No defaults. * SWITCH VD[c][a] Selects the ASCII character [c] and color attribute [a] of the read/write disk activity flash mediated by switch /TV+. Any ASCII character, except for those with code 10 (line feed), 13 ( return), or 26 (end-of-file) can be used for parameter <c>. The background/foreground video attribute <a> must be specified as a hexadecimal (base 16) digit pair between 00 and FF where the following values are recognized: 0 - black 8 - gray 1 - dim blue 9 - intense blue 2 - dim green A - intense green 3 - dim blue-green (cyan) B - intense blue-green 4 - dim red C - intense red 5 - dim blue-red (magenta) D - intense blue-red 6 - dim green-red (brown) E - intense green-red (yellow) 7 - dim white F - intense white No defaults. SWITCH VM Use if installing XDISK.SYS in a virtual machine of a multitasking system to prevent EMS losses if the virtual machine is ended. No defaults. COMMENTS -------- Comments may be added in the command line after the switches. The comments, which may be useful in annotating batch-file or CONFIG.SYS commands, must be preceded by a semicolon, and are ignored by xDISK. Do not use the DOS redirection and pipe characters in comments for XDISK.EXE commands since DOS will attempt to implement the implied redirection or pipe request. D. Status/Usage/Help panels Executing the program with switch /? selected allows access to the Status/ Usage and Help panels. (If a Mouse pointing device driver, compatible with the Microsoft Mouse driver version 6.0 or higher is loaded and active, all of the services provided by these panels can also be activated by pointing the mouse to specific areas of the screen and clicking either button. The mouse driver state is saved prior to the display, to be restored later, if sufficient memory is available.) The STATUS/USAGE panel, which is shown first, describes status information for the resident driver and its drive if an xDISK RAM-drive designator was specified, or a list of the installed xDISK RAM-drives if any. If a valid drive designator was specified, the STATUS subpanel also displays used and free kilobytes, and the value of the cluster from which DOS starts a free- space search when writing to the disk (see SWITCH DX above). The USAGE subpanel shows a menu for the command switches: To cycle between the main and the auxiliary menu, press key <F2> or <M>, or click the mouse upon the screen button labelled <Menu>. If the resident is installed, the status of some 'on/off' command switches is displayed by '+' or '-' before a given menu entry. The DATA subpanel shows the current drive parameters for the specified (or default) drive. Press key <F3> or <D>, or click the mouse upon the screen button labelled <Data> to display the panel; press the <Esc> key, or click the mouse upon the button labelled <Esc>, to return to the main panel. The following example was obtained from a 82%-full RAM-disk formatted with the switches /DB64 /DR16 /DS512 /TW+ /TR+ /TV+: █▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀█ █ Drive I, serial no. 3600-0009, label <xDISK I:> ┌──█ █ ╓▄└▄┐ █ █ Bytes/sector: 512 Medium ID type: F8h ║▀ ▀│ █ ═ [1] █ Sectors/cluster: 4 DOS-CDS linked: Yes ║Esc│ █ █ No. of FAT copies: 1 EMS pages used: 5 ╚═══╛ █ █ Sectors/FAT copy: 2 Disk compacted: Yes █ ═ [2] █ FAT entry length: 12-bit Safe expansion: +112 KB █ ═ [3] █ Root dir entries: 16 Safe shrinkage: -0 KB █ ═ [4] █ First root sector: 3 Write protect: Yes █ █ First user sector: 4 Resize protect: Yes █ █ Reserved sectors: 1 Drive feedback: Yes █ ═ [5] [6] ═ █ Free disk cluster: 34 Password check: No █ [7] ═ █ I/O disk accesses: 13157 █ [8] ═ █ I/O disk failures: 0 ▐▓▓▓▓▓▓▓░░░░░░░░░░░░░▌ █ █ 0 % Root Space 100 █ █ Used ▓ █ █ ▐▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓░░░░░░░░░▌ Free ░ █ █ 0 % Total Space 100 █ █▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█ NOTES: [1] Click a mouse on this mouse icon to cancel this display if the mouse is enabled, which is signalled by a beating <>. [2] Indicates whether there are empty gaps in the disk packing. [3] Number of additional KB that may be added to the disk size. [4] Number of KB that may be set free of the current disk size. [5] Indicates whether there is video <> and audio <> feedback during DOS-mediated read and write access to the disk. [6] Cluster at which MS-DOS will start searching for free space when writing to the disk. [7] Number of successful disk read and write requests from DOS. [8] Number of errors during read or write requests to the disk. The HELP panel provides a summary description of the program and commands, and is displayed if key <F1> or <H> is pressed from the Status/Usage panel (or if the mouse is clicked upon the screen button labelled <Help>). Press the keypad cursor keys (Home/End, PgUp/PgDn, arrows) to scroll the display down or up or the key <S> to scroll in a closed loop; alternatively, click the mouse upon the Up/Down arrows at the top right corner of the screen to scroll. Press key <F1> to skip the brief program summary and position the text on the Usage section directly. Pressing <F1> a second time positions the text on the Switches section directly. A beating icon to the left of the preceding USAGE panel controls the speed of screen scrolling of the HELP panel via key <S> or the mouse arrows. By positioning the mouse pointer over this beating icon and clicking the left or right mouse buttons, the rate of beating (and that of scrolling) can be respectively increased or decreased. Press key <Esc> or <F2>, or click the mouse upon the rightmost icon at the top left corner of the screen, to return to the Status/Usage panel. Press key <F7> or <X>, or click the mouse upon the leftmost icon, to exit to the DOS-prompt command line. If the program is waiting for keyboard (or mouse input) during the display of the Status/Usage panel, it issues the 'idle' interrupts of DOS, INT 28h and, if running under MS-DOS 5+, INT 2Fh, function 1680h, to allow for the the potential background activation of other residents. NOTE: (EGA users only) The default IBM palette attributes are restored if the EGA BIOS fails to store properly the original data. 5. BASIC TECHNICAL INFORMATION ------------------------------- A. DOS Errorlevels XDISK.EXE passes execution status data to DOS. These can be tested in batch files via the ERRORLEVEL command. The following are values for version 3.31 or later: Value Condition ----- -------------------------------------- 255 Cyclical Redundancy Check failure 254 286(386) version executed in non-286(386)+ machine 240 Error during driver unloading 238 Criticsal error opening driver 237 All drives are assigned (reached maximum) 236 All drives are assigned (increased limit) 235 Driver initialization error (command-line load) 234 Driver failed installation (command-line load) 233 Overlay of driver failed (command-line load) 232 Operating system does not support DOS function 32h 231 Failed to find NUL driver (command-line load) 230 Error during XDISK.SYS load (command-line load) 128 Unknown video card/video contents not preserved 65 Invalid EMS version 64 Invalid DOS version (1-2, 5; OS/2 DOS 10+) 36 Data loss on resize 35 Data-safe resize error 34 Format-protect resize error 33 Write-protect resize error 32 Resize request generic error 19 Evaluation period has expired 18 Open files left in disk 17 Temporary file acess error 16 Root directory full 8 Driver access eror 4 Invalid command/switch 2 Invalid character is password string 1 Bad/Invalid unit request 0 Succesful execution B. Disk Internals DOS can support several types of disk. Each disk contains information on its capabilities, which is stored on a specific area of the disk. In addition to this information, the disk must contain information necessary to the managing of the files and disk space, which is also stored in a reserved disk area. A DOS-compatible disk consists of 3 reserved areas and a user file area. The reserved areas are the Boot Sector, which contains a table of disk parameters used by DOS to manage disk space, and a bootstrap code to start the operating system; the File Allocation Table (FAT), containing data on file-space usage; and the Root Directory, containing size, location, date, and time information about the files on the disk. The surface of a (physical) disk is laid out as a series of concentric rings, called tracks, which are divided radially into sectors. When storing a file, a cluster is the basic unit of disk allocation used by DOS, and consists of a group of sectors, whose number varies with the disk type; the file is divided among as many sectors as are required to hold it. Whether just one or all of the sectors of a cluster are used, the cluster is marked as in use. In the FAT there is an entry for each cluster on the disk, containing a value that indicates the status of the cluster: reserved for DOS, free, in-use, bad and end of cluster chain. DOS stores cluster information as a cluster chain, in which each cluster points to the next cluster in use. Because the first 2 entries of the FAT are reserved, the first cluster of available disk space in the user file area is cluster number 2. The length of a FAT entry is either 12 or 16 bits, and it depends on the size of the disk in sectors and the cluster size; a 12-bit FAT entry is used until cluster values cannot be stored as a 12-bit quantity, which is when there are more than 4,079 clusters. The minimum disk size requiring 16-bit FAT entries can be calculated from: (4079 clusters x [sectors/cluster] x [bytes/sector]) = Disk size Improper FAT length entry due to modification of the above variables produces input/output disk errors; switch /DX monitors the variables to verify whether disk contents can be preserved or not. C. RAM-Disk Identification & DOS Version DOS assigns the first available drive letter to a RAM-disk within the default range A to E or, for DOS version 3 or higher, the range A to Z if the command <LASTDRIVE=Z> is included in CONFIG.SYS. Such a letter is shown by XDISK.SYS. xDISK drives can be identified by the volume label and the OEM identification in the boot sector, which are determined by the program version. If installed in a machine using an 80286 or a higher CPU, the disk date of creation is the current date in the CMOS chip; for an 8088/8086 CPU, such date is that of the assembly of XDISK.SYS. Similarly, the time of creation is the version number of the program when the driver is installed (e.g., 3:60 for version 3.60) for a machine using an 8088/8086 CPU, or the current time in the CMOS chip for an 80286 CPU. Afterward, the current time and date maintained by DOS are always used for the time/date creation stamp whenever the disk is reformatted. D. Self-Installation in Upper Memory The driver can install itself in the upper memory area (UMA), that is, at RAM addresses between 640 KB and 1024 KB of memory, via switch /H (or its subfunctions /Hn, /H[n]X, and /H[n]D). Program releases prior to version 3.10 lack this feature. The allocation of UMA blocks (UMBs) is arbitrated by an XMS manager (XMM) version 2.0 or higher; the XMM must be installed prior to the UMB-loading of the resident. Allocation also requires the remapping of UMA addresses by a UMB provider, when such a task is not implemented by the XMM itself. XMMs require MS-compatible DOS version 3.0 or later. HIMEM.SYS is the XMM distributed with MS-DOS 5+. Installation of this XMM and of a UMB provider (e.g. a 386-specific memory manager such as EMM386. EXE) allows DOS 5+ to control UMB allocation, provided that DOS access to the UMA is enabled. Other 386/486-specific memory managers, e.g. QEMM386 (Quarterdeck) or 386MAX (Qualitas), are able to provide UMB remapping and XMS support directly. Switch /Hn, where A000 ≤ n ≤ FFFF (hexadecimal), allows the specification of a minimum upper-memory limit for the UMB to avoid UMA regions having a very slow access time (or to preserve regions with a fast access time for other utilities that require faster times, such as a disk cache or screen accelerator), or to avoid fragmentation of the UMA when UMB allocation is not controlled by DOS 5+, but by the XMM itself. Such a fragmentation may occur when the XMM allocates blocks on a first-fit basis, i.e., the first available UMB having the lowest UMA address is allocated, irrespective of whether or not a (smaller) block matching the requested size is available at a higher UMA address. Unless the size of the available UMBs increases with increasing memory address, first-fit allocation of a small UMB could lead to the breaking of a large UMB into two smaller ones, thus hampering the installation of larger residents in the UMA. When DOS controls the UMB allocation, the program enforces the allocation of the resident block on a best-fit basis when <n> is not specified, that is, all available blocks are searched (by DOS), and the one matching most closely the size requested is allocated. When DOS controls UMB allocation and <n> is specified, UMBs are allocated on a first-fit basis. While this may contribute to UMA fragmentation, it allows for the checking of a minimum memory limit in those cases in which the selection or avoidance of a specific UMA region is more important. Thus, compared to the UMB loading provided by the command 'DEVICEHIGH' of MS-DOS 5+, the command 'HIDEVICE' of DR-DOS 6.00, or the similar services provided by some 386/486-specific memory managers, selfloading into a UMB has some advantages, including (1) it requires only an initial free block of upper memory of the size of the resident code only (as opposed to that of the entire program), (2) it permits more user control of the selection of the upper-memory block, and (3) it can help reduce UMA fragmentation. Due to the manner in which 'DEVICEHIGH' changes the UMA allocation chain, do not use this command in any line preceeding that which installs xDISK, if the UMB selfload switch /LH has been specified (see above). Of course, the resident can also be installed in the UMA via a 386-memory manager or via UMB-linked MS-DOS 5+, provided that there is enough memory for the actual size of the entire program, and any additional memory that may be needed by the loading utility. The driver XDISK.SYS is an uncompressed file, while the interface utility XDISK.EXE is a compressed file (that self-expands by a factor of 2 during execution). Note ------------------------------------------------------------------- The address and size of available UMBs can be obtained via MEM.EXE, when DOS controls UMB allocation, or via the memory manager itself, when this allocation is controlled by 386-specific memory managers. In either case, such data can also be obtained with UMAX.EXE, a UMA mapping utility that is distributed by the author. If memory access time is a critical element in the selection of the UMBs, a detailed timing access map is provided by TIMEM.EXE, a utility which is also distributed by the author. ------------------------------------------------------------------- E. xDISK Communication Interface Starting with version 3.32, xDISK implements an interface via interrupt 2Fh, which allows communication with the driver. A description of this interface is provided below in case you want your programs to detect whether the xDISK driver is loaded in memory or if a given unit is an xDISK drive: Registers at call: AH = 0DDh Interrupt 2Fh subfunction used by xDISK AL = 0/1-26 Drive unit (1-26) or installation check (0) BX = 7844h API signature ("xD") CX = 7844h ("IS") DX = 7844h ("K?") ES:DI -> Pointer to 25-byte minimum length data buffer Return registers if successful: CF = ? Undetermined AX = 0DDFFh BX = 87BBh One's complement of signature (NOT "xD") CX = ? Register not preserved DX = B4C0h One's complement of signature (NOT "K?") ES:[DI+0] = offset of driver signature for unit in [AL] ES:[DI+2] = segment of (paragraph-aligned) driver address ES:[DI+4] = start of data list (19 bytes) To verify if a given drive is an xDISK unit, place the unit code (1=A, 2=B, 3=C, etc) in AL; to verify if any xDISK driver is installed, place 0 in AL. At installation time, xDISK checks whether the INT-2F vector is a null one; if so, it replaces this vector for one that points to an IRET instruction. If the xDISK driver is installed, the INT-2F call returns with the contents of AL = FFh, and the one's complement of the interface signature components in BX and DX. The contents of CX are not preserved. The paragraph-aligned (base) segment of the driver is returned in the word starting at ES:[DI+2]. If further verification is required, the far address returned in the double word starting at ES:[DI] points to the offset of the following string: DB "xDISK unit: " ; 12-byte ID string DB ? ; drive unit letter (A-Z) DB 0 ; end of ASCIIz string The status of the following static driver flags is returned starting at ES: [DI+4] through [DI+23]: Offset 04h 1=DOS linked, 0=DOS unlinked disk Offset 05h 1=write protected, 0=not protected Offset 06h 1=root directory full, 0=not full Offset 07h 1=uncompacted free space, 0=compacted Offset 08h 1=resized, 80h=resizable, 0=not resizable Offset 09h 1=inelastic resizable disk, 0=elastic disk Offset 0Ah ? (reserved) Offset 0Bh ? (reserved) Offset 0Ch 1=collapsed disk, 0=not collapsed Offset 0Dh 1=using all EMS, 0=using some EMS Offset 0Eh 1=password enabled, 0=password disabled Offset 0Fh 1=password audio feedback, 0=no feedback Offset 10h 1=password video feedback, 0=no feedback Offset 11h 1=confirm changes first, 0=no confirm Offset 12h 1=silent display, 0=verbose display Offset 13h 1=click speaker on disk access, 0=no click Offset 14h 1=flash symbol on disk access, 0=no flash Offset 15h 0=12 bit, FFh=16 bit: length of FAT entries Offset 16h ? (reserved) 6. COPYRIGHT & LICENSE INFORMATION ---------------------------------- This documentation, programs, and other files distributed in this software package (the "Software") are the copyrighted property of FM de Monasterio (the "Author"), who provides the Software and licenses its use. All rights are reserved. The Software is not sold. A license fee is required to use this Software. This license does not transfer to you either the ownership of or the title to the Software, which remain the property of the Author. A form required to license the Software is provided in the enclosed file XDISK.REG SINGLE USER LICENSE. Grants you use of this Software in a single computer at a time; the Software may be transferred to another computer, as long as it is used only in 1 computer at any time; under the license, the Software may NOT be installed on a network server. SITE/15-PCs LICENSE. Grants you use of this Software in a sigle site or a set of sites, as long as the Software is not used in more than 15 machines at a time, and that such machines are located exclusively within the site. Licenses for more machines are available at discounted prices. SOFTWARE BUNDLING LICENSE. Please write to the Author. REFUNDS POLICY. If a problem notified within ninety (90) days of shipping of the registered copy cannot be solved, the registration fee (but not the shipping costs) will be refunded upon receiving a written request with the original diskette(s) enclosed. UPGRADE POLICY. Program upgrades are limited to licensed users. Upgrades within the same major version (e.g. release 4.00 through 4.99) are free of charge when a self-addressed, stamped, 5.25" diskette mailer with a 360-KB diskette is included with the request. Other upgrades are charged half the (single-user/site) registration fee. See the enclosed file XDISK.UPG. U.S. GOVERNMENT INFORMATION The Software is Commercial Computer Software under the Federal Acquisition Regulations of the U.S. government and the Agency Supplements to them. The Software is provided to the Federal Government and its agencies only under the Restricted Rights Provisions of the above noted regulations applicable to commercial software developed at private expense, and not in the public domain. The use, duplication, or disclosure of the Software by the Federal Government or its agencies is subject to the restrictions set forth in the subdivision (c.1.ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013 (October 1988) and FAR 52.227-19 (June 1987). DISTRIBUTION You may distribute the Software, but you are specifically prohibited from: - Charging fees or asking donations in exchange of or payment for copies of this Software. - Distributing this Software with commercial products without the written, express permission in advance from the author. - Distributing this Software via a for-profit organization or group, either alone or with other software. - Changing any of the contents of this Software including the copyright notice and license information. You may not disassemble or otherwise reverse engineer the Software. Other uses of the Software are prohibited without a written authorization signed by the Author. Latest program releases may be found at the Information Exchange BBS (703) 836-0748, as a compressed archive file. WARRANTY DISCLAIMER FOR UNREGISTERED COPIES The information contained in the documentation for the Software is subject to change without notice. The Author cannot and does not warrant that any functions contained in the Software will meet your requirements, or that its operations will be error free. The entire risk as to the Software performance or quality, or both, is solely with the user and not the Author. You assume responsibility for the selection of the Software to achieve your intended results and for the installation, use, and results obtained from the Software. The Author makes no warranty, either implied or expressed, including with- out limitation any warranty with respect to this Software documented here, its quality, performance, or fitness for a particular purpose. In no event shall the Author be liable to you for damages, whether direct or indirect, incidental, special, or consequential arising out the use of or any defect in the Software, even if the Author has been advised of the possibility of such damages, or for any claim by any other party. All other warranties of any kind, either express or implied, including but not limited to the implied warranties of merchantability and fitness for a particular purpose, are expressly excluded. By using the Software, you acknowledge (1) to have read and understood all parts of this document and (2) to have agreed with and accepted all of its terms and provisions without any reservation. For information on the terms of the Limited Warranty for licensed Software copies or any other information on this program, please write to: FM de Monasterio P.O. Box 219 Cabin John, MD 20818-0219 USA ┌─────────────────────────────────────────────────────────────┐ │ Trademarked names are the property of the respective owners │ └─────────────────────────────────────────────────────────────┘ [END]