Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM. |
IMGBK
Control Block Contents
IMGBK DSECT
Cross Reference (Contains links to field and bit definitions)
IMGBK Prolog
NAME : HCPIMGBK DESCRIPTION: Image library/NLS Message Repository Block DSECT : IMGBK FUNCTION : This block is used for communications purposes when CP users request access to an Image library or NLS message repository file. LOCATED BY : (Images) Pointer in RSPBK (NLS) Pointer in LNGBK CREATED BY : (Images) HCPSIL - when a printer is started (NLS) HCPNLS - when the first user requests the language DELETED BY : (Images) HCPSIL - when a printer is drained (NLS) HCPNLS - when the last user releases the language SERIALIZED : Individual IMGBKs are serialized by holding the symbolic lock on the filename of the item. All image, NLS, NSS and DCSS system data files are locked/unlocked with the same lockword (NSUSYMAN), using entry points HCPLOCPQ/HCPLOCPD. SNTBKs for image libraries and NLS files are kept on the same queue, anchored in HCPIMGLK. This queue is locked/unlocked via the macros HCPLKIMG/HCPULIMG. COMMENTS : This is a variable length control block. It consists of the header information plus a variable number of virtual addresses.
IMGBK Control Block Content
IMGBK DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure IMGBK Image library/NLS Message Repository 0000 0 Address 4 IMGSNTBK Pointer to the SNTBK 0004 4 Signed 2 IMGDWSZE Size in doublewords of the block 0006 6 Bitstring 1 IMGTYPFG What type of file is this? .... ...1 IMGIMAGE X'01' Image library file .... ..1. IMGNLS X'02' NLS Message Repository file 0007 7 Bitstring 1 IMGFLAGS Miscellaneous Status Flags .... ...1 IMGFIRST X'01' First open for this file, set and reset by HCPNSROP. 0008 8 Address 4 IMGCPNTL Address of a CP resident routine to be called when the last user releases the image library or NLS language file. When field is zero, no call is made. 000C 12 Address 4 IMGLNGBK Pointer to LNGBK for this language. (For NLS language files only; for image libraries it does not apply, and remains zero. 0010 16 Character 8 IMGNAME File name of the image library or NLS language file 0018 24 Signed 4 IMGRECNO Number of the first record to be read. Records are numbered starting from one (1). 001C 28 Signed 4 IMGRECCT Count of records to be read 00000004 IMGHDRSZ ((*-IMGBK)+7)/8 Header size in doublewords 0020 32 Signed 4 IMGVADDR (0) Start of variable length data 0020 32 Signed 4 IMGVIRT Returned system virtual address
IMGBK Storage Layout
*** IMGBK - Image library/NLS Message Repository * * +---------------------------+-------------+------+------+ * 0 | IMGSNTBK | IMGDWSZE |:TYPFG|:FLAGS| * +---------------------------+-------------+------+------+ * 8 | IMGCPNTL | IMGLNGBK | * +---------------------------+---------------------------+ * 10 | IMGNAME | * +---------------------------+---------------------------+ * 18 | IMGRECNO | IMGRECCT | * +---------------------------+---------------------------+ * *** IMGBK - Image library/NLS Message Repository *** Overlay for IMGVADDR in IMGBK * * +---------------------------+ * 20 | IMGVIRT | 24 * +---------------------------+ * *** Overlay for IMGVADDR in IMGBK
IMGBK Cross Reference
Symbol Dspl Value -------------- ---- ----- IMGCPNTL 0008 IMGDWSZE 0004 IMGFIRST 0007 01 IMGFLAGS 0007 IMGHDRSZ 001C 00000004 IMGIMAGE 0006 01 IMGLNGBK 000C IMGNAME 0010 IMGNLS 0006 02 IMGRECCT 001C IMGRECNO 0018 IMGSNTBK 0000 IMGTYPFG 0006 IMGVADDR 0020 IMGVIRT 0020
Last updated on 5 Jun 2001 at 13:56:11 EDT.
Copyright IBM Corporation, 1990, 2001