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Programming Interface Information:
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Interfaces that allow the customer to write programs to obtain the services of VM/ESA. |
FSCBD
Cross Reference (Contains links to field and bit definitions)
FSCBD Prolog
NAME : FSCBD Description: File System Control Block DSECT : FSCBD Function : Maps a based structure which names all fields within an FSCB. FSCBD is a PLIST defined for general use by routines that use the CMS file system. FSCBD is generated when the user issues the FSCBD macro.
FSCBD Control Block Content
FSCBD DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure FSCBD File System Control Block 0000 0 Character 8 FSCBCOMM File system command (e.g. RDBUF) 0008 8 Character 18 FSCBFILE File ID (name, type, and mode) 0008 8 Character 16 FSCBFNFT File name and file type 0008 8 Character 8 FSCBFN File name 0010 16 Character 8 FSCBFT File type 0018 24 Character 2 FSCBFM File mode (letter and number) 0018 24 Character 1 FSCBFML File mode letter 0019 25 Character 1 FSCBFMN File mode number 001A 26 Signed 2 FSCBITNO Relative record number to be accessed on FSREAD and FSWRITE (applies only to the non-extended FSCB) 001C 28 Address 4 FSCBBUFF Address of the input/output buffer for FSREAD and FSWRITE (also used on calls to DMSSTT for the FST address) 0020 32 Signed 4 FSCBSIZE Length (in bytes) of the input/output buffer (also used to return the record length on FSOPEN) 0024 36 Character 2 FSCBFV Record format and first flag byte 0024 36 Character 1 FSCBRECF Record format - F or V 0025 37 Bitstring 1 FSCBFLG First flag byte 'FSCBFLG' flag byte definition 1... .... FSCBTHEX X'80' Space threshold exceeded (SFS only) .1.. .... FSCBITAV X'40' Item available (CDF only) ..1. .... FSCBEPL X'20' Extended PLIST (FORM=E) ...1 .... FSCBMSG X'10' MSG=YES on FSSTATE or FSOPEN .... 1... FSCBSTW X'08' STATEW specified on FSSTATE .... .1.. FSCBCACY X'04' CACHE=YES specified .... ..1. FSCBCACN X'02' CACHE=NO specified .... ...1 FSCBRCAV X'01' Previous record null (CDF only) 0026 38 Signed 2 FSCBNOIT Number of records to be accessed on FSREAD and FSWRITE (applies only to the non-extended FSCB) 0026 38 Bitstring 1 FSCBFLG2 Second flag byte 'FSCBFLG2' flag byte definition (FORM=E only) 1... .... FSCBNMAC X'80' NOMSG=ACTIVE specified on FSOPEN .1.. .... FSCBNMNF X'40' NOMSG=NOTFOUND specified on FSOPEN ..1. .... FSCBNMOS X'20' NOMSG=OSDOS specified on FSOPEN 0027 39 Character 1 FSCBOTYP OPENTYP value 'FSCBOTYP' Values (FORM=E only) .... .... FSCBTNON X'00' OPENTYP=NONE specified 000000D9 FSCBTRD C'R' OPENTYP=READ specified 000000E6 FSCBTWR C'W' OPENTYP=WRITE specified 000000D5 FSCBTNEW C'N' OPENTYP=NEW specified 000000E7 FSCBTREP C'X' OPENTYP=REPLACE specified 0028 40 Signed 4 FSCBNORD Number of bytes actually read on FSREAD 'FSCBFST' is returned on FSOPEN. Its value is based on the OPENTYP specified and whether or not the file exists. Note that a non-extended format FSCB (FORM=E not specified) implies OPENTYP=NONE. The values are as follows: File doesn't exist .... FSCBFST=A(0) File exists: Not FORM=E ............ FSCBFST=A(Copy of 40 byte FST) OPENTYP=NONE .......... FSCBFST=A(Copy of 64 byte FST) OPENTYP=READ .......... FSCBFST=A(Copy of 64 byte FST) OPENTYP=WRITE ......... FSCBFST=A(Copy of 64 byte FST) OPENTYP=REPLACE ....... FSCBFST=A(-1) OPENTYP=NEW ........... Error, FSCBFST is unchanged 0028 40 Address 4 FSCBFST Address of a copy of the FST returned on FSOPEN The following fields apply only to the extended form FSCB (i.e., FORM=E was specified). 002C 44 Signed 4 FSCBAITN Relative record number to be accessed on FSREAD and FSWRITE (also referred to as the "alternate item number") 0030 48 Signed 4 FSCBANIT Number of records to be accessed on FSREAD and FSWRITE (also referred to as the "alternate number of items") 0034 52 Signed 4 FSCBWPTR Extended write pointer (input on FSPOINT FORM=E, output on FSOPEN) 0038 56 Signed 4 FSCBRPTR Extended read pointer (input on FSPOINT FORM=E, output on FSOPEN) 0000003C FSCBLNBY *-FSCBD Length (in bytes) of the extended FSCB
FSCBD Storage Layout
*** FSCBD - File System Control Block * * +-------------------------------------------------------+ * 0 | FSCBCOMM | * +-------------------------------------------------------+ * 8 | | * = FSCBFILE = * | +-----------------------------------------+ * | | 1A * +-------------+ * *** FSCBD - File System Control Block *** Overlay for FSCBFILE in FSCBD * * +-------------------------------------------------------+ * 8 | FSCBFNFT | * | | * +-------------------------------------------------------+ * 18 * *** Overlay for FSCBFILE in FSCBD *** Overlay for FSCBFNFT in FSCBD * * +-------------------------------------------------------+ * 8 | FSCBFN | * +-------------------------------------------------------+ * 10 | FSCBFT | * +-------------+-----------------------------------------+ * 18 | FSCBFM | 1A * +-------------+ * *** Overlay for FSCBFNFT in FSCBD *** Overlay for FSCBFM in FSCBD * * +------+------+-------------+---------------------------+ * 18 |:BFML |:BFMN | FSCBITNO | FSCBBUFF | * +------+------+-------------+-------------+-------------+ * 20 | FSCBSIZE | FSCBFV | 26 * +---------------------------+-------------+ * *** Overlay for FSCBFM in FSCBD *** Overlay for FSCBFV in FSCBD * * +------+------+-------------+ * 20 ... 24 |:BRECF|:BFLG | FSCBNOIT | * +------+------+-------------+ * 28 * *** Overlay for FSCBFV in FSCBD *** Overlay for FSCBNOIT in FSCBD * * +------+------+ * 20 ... 26 |:BFLG2|:BOTYP| * +---------------------------+-------------+------+------+ * 28 | FSCBNORD | 2C * +---------------------------+ * *** Overlay for FSCBNOIT in FSCBD *** Overlay for FSCBNORD in FSCBD * * +---------------------------+---------------------------+ * 28 | FSCBFST | FSCBAITN | * +---------------------------+---------------------------+ * 30 | FSCBANIT | FSCBWPTR | * +---------------------------+---------------------------+ * 38 | FSCBRPTR | 3C * +---------------------------+ * *** Overlay for FSCBNORD in FSCBD
FSCBD Cross Reference
(contains links to field and bit definitions)Symbol Dspl Value -------------- ---- -----FSCBAITN 002C
FSCBANIT 0030
FSCBBUFF 001C
FSCBCACN 0025 02
FSCBCACY 0025 04
FSCBCOMM 0000
FSCBEPL 0025 20
FSCBFILE 0008
FSCBFLG 0025
FSCBFLG2 0026
FSCBFM 0018
FSCBFML 0018
FSCBFMN 0019
FSCBFN 0008
FSCBFNFT 0008
FSCBFST 0028
FSCBFT 0010
FSCBFV 0024
FSCBITAV 0025 40
FSCBITNO 001A
FSCBLNBY 0038 0000003C
FSCBMSG 0025 10
FSCBNMAC 0026 80
FSCBNMNF 0026 40
FSCBNMOS 0026 20
FSCBNOIT 0026
FSCBNORD 0028
FSCBOTYP 0027
FSCBRCAV 0025 01
FSCBRECF 0024
FSCBRPTR 0038
FSCBSIZE 0020
FSCBSTW 0025 08
FSCBTHEX 0025 80
FSCBTNEW 0027 000000D5
FSCBTNON 0027 00
FSCBTRD 0027 000000D9
FSCBTREP 0027 000000E7
FSCBTWR 0027 000000E6
FSCBWPTR 0034
Last updated on 12 Aug 1999 at 11:22:47 EDT.
Copyright IBM Corporation, 1990, 1999