This is part of Family API which allow to create dual-os version of program runs under OS/2 and DOS

Note: This is legacy API call. It is recommended to use 32-bit equivalent

Name	Description	Cross-platform
BadDynLink	This is DOS specific version function which called during module loading if linking error is detected. It shows message and terminates via int 21h Terminate call	-
DosBeep	Generate sound from the speaker using direct port I/O	No
DosBufReset	Flushes a file cache buffers
DosChDir	Defines the current directory for the requesting process
DosChgFilePtr	Moves the read/write pointer
DosClose	Closes a handle to a file, pipe, or device
DosCreateCSAlias	Create CS alias from data segment
DosCLIAccess	Request I/O privilege for disabling and enabling interrupts
DosPortAccess	Request or release access to ports for I/O privilege
DosDelete	Removes a directory entry associated with a file name
DosDevConfig	Return device configuration
DosDupHandle	Returns a new file handle for an open file
DosFreeSeg	Deallocates a memory segment
DosGetDateTime	Get the current date and time
DosGetEnv	Return process environment for the current process from LocalInfoSeg	Yes
DosGetHugeShift	Return a shift count used to derive the selectors that address memory allocated with DosAllocHuge
DosGetMachineMode	Returns the current mode of the processor
DosGetMessage	Retrieve a message from the specified system message file
DosGetVersion	Return the OS version number via GlobalInfoSeg	Yes
DosInsMessage	Insert variable text string information into the body of a message
DosMkDir	Create a subdirectory
DosMkDir2	Create a subdirectory with EA
DosMove	Move a file object to another location, change its name
DosNewSize	Changes the size of a file
DosPutMessage	Output the message
DosQCurDir	Returns the full path name of the current directory
DosQCurDisk	Determines the current default drive for the requesting process
DosQFileMode	Queries the mode (attribute) of the specified file
DosQFSInfo	Query file system info
DosQVerify	Returns the value of the verify flag
DosRmDir	Removes a subdirectory from the specified disk
DosSelectDisk	Selects the drive specified as the default drive
DosSetDateTime	Set the date and time
DosSetFileInfo	Set attribute and extended attribute information for a file
DosSetFileMode	Changes the mode (attribute) of the specified file
DosSetVerify	Sets write verification
DosSleep	Suspend the current thread for a specified time
DosSubAlloc	Suballocate portions of a segment
DosSubFree	Free memory previously allocated by DosSubAlloc
DosSubSet	Initialize a segment for suballocation
DosWrite	Write buffer to file
DosAllocHuge	Allocate multiple segments as a huge block of memory
DosAllocSeg	Allocate a data segment up to 64KB in size
DosCaseMap	Case mapping on a string
DosDevIOCtl	Control functions on a device
DosDevIOCtl2	Control functions on a device
DosError	Receive hard error notification
DosErrClass	Receive hard error code information
DosExecPgm	Execute another program as a child process
DosExit	End The current thread or process
DosFileLocks	Locks and unlock a range in an opened file
DosFindClose	Finish DosFindFirst or DosFindNext directory search function sequence
DosFindFirst	Finds the first file object or group of file objects whose name(s) match the specification
DosFindFirst2	Finds the first file object or group of file objects whose name(s) match the specification
DosFindNext	Locate the next set of directory entries
DosGetCtryInfo	Obtain country-dependent formatting information that resides in the country information file
DosGetDBCSEv	Obtain a DBCS (double byte character set) environmental vector that resides in the country information file
DosGetCP	Query the current process code page and the prepared system code pages
DosSetCP	Set process code page and the session's display code page and keyboard code page
DosGetCollate	Obtain a collating sequence table
DosHoldSignal	Temporarily disable or enable signal processing for the current process
DosOpen	Open a file, a named pipe, or a device
DosOpen2	Open a file with extended attributes
DosQFileInfo	Return information for a specific file
DosRead	Read the specified number of bytes from a file, pipe, or device to a buffer location
DosReallocHuge	Change the size of memory originally allocated by DosAllocHuge
DosReallocSeg	Reallocate a segment after discard or changes the size of a segment already allocated
DosSetCtryCode
DosSetFHandState	Set the state of the specified file
DosSetSigHandler	Set signal handler
DosAllocShrSeg	Allocate a named shared memory segment to a process
DosGetShrSeg	Accesses a shared memory segment previously allocated by another process
DosLoadModule	Load a dynamic link module and returns a handle for the module
DosFreeModule	Free the reference to a dynamic link module for a process
DosQHandType	Get handle type
DosGetProcAddr	Get module procedure address
DosGetPID	Get process id
DosSetMaxFH	Set maximum file handlers
DosGetModHandle	Get module handle
DosQPathInfo	Get path information
DosQFSAttach	Query information about an attached file system
DosQSysInfo	Query system variablies values
DosMemAvail	Query maximum availabe huge memory block
DosGetInfoSeg	Query global and local information segments
KbdCharIn	Return a character data record from the keyboard
KbdFlushBuffer	Clear the keystroke buffer
KbdGetStatus	Get the current state of the keyboard
KbdSetStatus	Set the characteristics of the keyboard
KbdStringIn	Read a character string (character codes only) from the keyboard
KbdPeek	Return any available character data record from the keyboard without removing it from the buffer
KbdOpen	Create a new logical keyboard
KbdClose	Close the existing logical keyboard
KbdGetFocus
KbdFreeFocus
KbdGetCp
KbdSetCp
KbdXlate
KbdSetCustXt
KbdGetHWId
KbdRegister
KbdDeRegister
MouRegister
MouDeRegister
MouGetNumButtons
MouGetNumMickeys
MouGetDevStatus
MouGetNumQueEl
MouReadEventQue
MouGetScaleFact
MouGetEventMask
MouSetScaleFact
MouSetEventMask
MouGetHotKey
MouSetHotKey
MouOpen
MouClose
MouGetPtrShape
MouSetPtrShape
MouDrawPtr
MouRemovePtr
MouGetPtrPos
MouSetPtrPos
MouInitReal
MouFlushQue
MouSetDevStatus
VioGetBuf	Return the address of the logical video buffer (LVB)
VioGetCurPos	Return the coordinates of the cursor
VioGetCurType	Get cursor type
VioGetPhysBuf	Get addressability to the physical display buffer
VioReadCellStr	Read a string of character-attribute pairs from the screen
VioReadCharStr	Read a string of characters from the display
VioScrollDn	Scroll the entire display buffer (or area specified within the display buffer) down
VioScrollLf	Scroll the entire display buffer (or area specified within the display buffer) to the left
VioScrollRt	Scroll the entire display buffer (or area specified within the display buffer) to the right
VioScrUnLock	Release ownership of (unlocks) the physical display buffer
VioSetCurPos	Set the cursor's coordinates on the screen
VioSetCurType	Set the cursor type
VioSetMode	Set the mode of the display
VioShowBuf	Update the physical display buffer with the logical video buffer (LVB)
VioWrtCellStr	Write a string of character-attribute pairs (cells) to the display
VioWrtCharStr	Write a character string to the display
VioWrtCharStrAtt	Write a character string with repeated attribute to the display
VioWrtNAttr	Write an attribute to the display a specified number of times
VioWrtNCell	Write a cell (character-attribute pair) to the display a specified number of times
VioWrtNChar	Write a character to the display a specified number of times
VioWrtTTY	Write a character string to the display starting at the current cursor position
VioScrLock	Request ownership of (locks) the physical display buffer
VioGetMode	Return the mode of the display
VioGetConfig	Return the video display configuration
VioGetAnsi	Return the current ANSI status On/Off state
VioSetAnsi	Activate or deactivate ANSI support
VioScrollUp	Sroll the entire display buffer (or area specified within the display buffer) up
VioDeRegister	Deregister alternate video system
VioRegister	Register alternate video system
VioGetState	Return the current settings of adapter
VioSetState	Set the current settings of adapter
VioGetCP	Query the code page for display
VioSetCP	Set the code page for display
VioGetFont	Get current font
VioSetFont	Set current font
VioModeWait	Notify process about it must restore its video mode
VioModeUndo
VioPopUp	Show temporary screen to display message
VioEndPopUp	Return from temporary screen
VioSavRedrawWait	Notifies application when it must save/redraw its screen
VioSavRedrawUndo
VioPrtSc	Dump screen to printer
VioPrtScToggle	Toggle VioWrtTty also write to printer