Table B-1 lists the I/O functions and function modifiers supported for the DECram for OpenVMS driver.

Table B-1 DECram I/O Functions

Function Code	Arguments	Type1	Function Modifiers	Function
IO$_ACCESS	P1,[P2],[P3],[P4],[P5]	V	IO$M_CREATE IO$M_ACCESS	Search a directory for a specified file and access the file if found.
IO$_ACPCONTROL	P1,[P2],[P3],[P4],[P5]	V	IO$M_DMOUNT	Perform miscellaneous control functions.
IO$_AVAILABLE		P		Clear volume valid; make DSA 2 units available.
IO$_CREATE	P1,[P2],[P3],[P4],[P5]	V	IO$M_CREATE IO$M_ACCESS IO$M_DELETE	Create a directory entry or a file.
IO$_DEACCESS	P1,[P2],[P3],[P4],[P5]	V		Deaccess a file and, if specified, write final attributes in the file header.
IO$_DELETE	P1,[P2],[P3],[P4],[P5]	V	IO$M_DELETE	Remove a directory entry or file header, or both.
IO$_MODIFY	P1,[P2],[P3],[P4],[P5]	V		Modify the file attributes or allocation, or both.
IO$_PACKACK		P		Update UCB 3 fields if RX02; initialize volume valid on other devices. Bring DSA units online.
IO$_READLBLK	P1,P2,P3	L	IO$M_DATACHECK IO$M_INHRETRY	Read logical block.
IO$_READPBLK	P1,P2,P3	P	IO$M_DATACHECK IO$M_INHRETRY IO$M_INHSEEK	Read physical block.
IO$_READVBLK	P1,P2,P3	V	IO$M_DATACHECK IO$M_INHRETRY	Read virtual block.
IO$_SENSECHAR		P		Sense the device-dependent characteristics and return them in the I/O status block.
IO$_SENSEMODE		L		Sense the device-dependent characteristics and return them in the I/O status block.
IO$_UNLOAD		P		Clear volume valid; make DSA units available and spin down the volume.
IO$_WRITELBLK	P1,P2,P3	L	IO$M_DATACHECK IO$M_ERASE IO$M_INHRETRY	Write logical block.
IO$_WRITEPBLK	P1,P2,P3	P	IO$M_DATACHECK IO$M_ERASE IO$M_INHRETRY IO$M_INHSEEK	Write physical block.
IO$_WRITEVBLK	P1,P2,P3	V	IO$M_DATACHECK IO$M_ERASE IO$M_INHRETRY	Write virtual block.