gs_name_64 OpenVMS usage:section_name type: character-coded text string access: read only mechanism: by 32- or 64-bit descriptor-fixed-length string descriptor Name of the global section. The gs_name_64 argument is the 64- bit virtual address of a naturally aligned 32- or 64-bit string descriptor pointing to this name string. ident_64 OpenVMS usage:section_id type: quadword (unsigned) access: read only mechanism: by 32- or 64-bit reference Identification value specifying the version number of a global section. The ident_64 argument is a quadword containing three fields. The ident_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword that contains the identification value. The first longword specifies the matching criteria in its low- order two bits. The valid values, symbolic names by which they can be specified, and their meanings are as follows: Symbolic Value Name Match Criteria 0 SEC$K_MATALL Match all versions of the section. 1 SEC$K_MATEQU Match only if major and minor identifications match. 2 SEC$K_MATLEQ Match if the major identifications are equal and the minor identification of the mapper is less than or equal to the minor identification of the global section. If you specify the ident_64 argument as 0, the version number and match control fields default to 0. The version number is in the second longword and contains two fields: a minor identification in the low-order 24 bits and a major identification in the high-order 8 bits. You can assign values for these fields by installation convention to differentiate versions of global sections. If no version number is specified when a section is created, processes that specify a version number when mapping cannot access the global section. file_offset_64 OpenVMS usage:byte offset type: quadword (unsigned) access: read only mechanism: by value Byte offset into the file that marks the beginning of the section. The file_offset_64 argument is a quadword containing this number. If you do not specify the file_offset_64 argument or specify it as 0, the section is created beginning with the first byte in the file. The file_offset_64 argument must be a multiple of virtual disk blocks. length_64 OpenVMS usage:byte count type: quadword (unsigned) access: read only mechanism: by value Length, in bytes, of the global disk file section to be created. The length specified must be 0 or a multiple of virtual disk blocks. If the length specified is 0 or extends beyond end-of- file (EOF), the global disk file section is created up to and including the virtual block number that contains EOF. chan OpenVMS usage:longword type: longword (unsigned) access: read only mechanism: by value Number of the channel on which the file has been accessed. The chan argument is a longword containing this number. The access mode at which the channel was opened must be equal to or less privileged than the access mode of the caller. You can use the OpenVMS Record Management Services (RMS) macro $OPEN to access a file; the file options parameter in the file access block must indicate a user file open (UFO keyword). acmode OpenVMS usage:access_mode type: longword (unsigned) access: read only mechanism: by value Access mode that is to be the owner of the pages created during the mapping. The acmode argument is a longword containing the access mode. The $PSLDEF macro in STARLET.MLB and the file PSLDEF.H in SYS$STARLET_C.TLB define the following symbols and their values for the four access modes: Value Symbolic Name Access Mode 0 PSL$C_KERNEL Kernel 1 PSL$C_EXEC Executive 2 PSL$C_SUPER Supervisor 3 PSL$C_USER User flags OpenVMS usage:mask_longword type: longword (unsigned) access: read only mechanism: by value Flag mask specifying the type of global section to be created as well as its characteristics. The flags argument is a longword bit vector in which each bit corresponds to a flag. The $SECDEF macro and the SECDEF.H file define a symbolic name for each flag. You construct the flags argument by performing a logical OR operation on the symbol names for all desired flags. The following table describes each flag that is valid for the $CREATE_GFILE service: Flag Description SEC$M_CRF Pages are copy-on-reference. By default, pages are shared. SEC$M_DZRO Pages are demand-zero pages. By default, they are not zeroed when copied. Note that SEC$M_DZRO and SEC$M_CRF cannot both be set and that SEC$M_DZRO set and SEC$M_WRT clear is an invalid combination. SEC$M_GBL Pages form a global section. By default, this flag is always present in this service and cannot be disabled. SEC$M_PERM Global section is permanent. By default, this flag is always present in this service and cannot be disabled. SEC$M_SYSGBL Pages form a system global section. By default, pages form a group global section. SEC$M_WRT Pages form a read/write section. By default, pages form a read-only section. All other bits in the flags argument are reserved for future use by VSI and should be specified as 0. The condition value SS$_IVSECFLG is returned if any undefined bits are set or if an illegal combination of flags is set. return_length_64 OpenVMS usage:byte count type: quadword (unsigned) access: write only mechanism: by 32- or 64-bit reference The length of the global section created. The return_length_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the length of the global section in bytes. fault_cluster OpenVMS usage:byte count type: longword (unsigned) access: read only mechanism: by value Page fault cluster in byte units indicating how many pages are to be brought into memory when a page fault occurs for a single page. The fault cluster specified is rounded up to a multiple of CPU-specific pages. If this argument is specified as 0, the system default page fault cluster is used. If this argument is specified as more than the maximum allowed for the system, no error is returned. The systemwide maximum is used.