ZIP containers

The BS2ZIP application enables ZIP containers to be created on BS2000 systems, and files to be added to and extracted from these containers. The ZIP compression used is the Zlib method.

This application is also able to read ZIP containers built on foreign platforms (Windows, Unix systems, Linux) provided they use the Zlib compression method and provided they are compliant with PKZIP 4.5 or GZIP.

The containers created in BS2000 can also be reopened on foreign platforms if they were created in WinZip-compatible format.

The command to start the BS2ZIP application is /START-ZIP-MANAGER or /START-ZIP.

After starting the application, the user has to open an existing container or to create a new one with the OPEN-ZIP-CONTAINER statement. In the case of the creation of a new container the user has to select the appropriate container format (operand FORMAT of the statement) according to the usage planned for the container to be created.

Please respect the following rules to select the appropriate format:

1. Container creation :

   • if you plan to use the container on BS2000 platforms only, you can create it in BS2000 format However, if you zip SAM or ISAM file including special print control characters, use the BS2000 format.

   • if you plan to export the container on foreign platforms, create your container in *WINZIP compatible format (default one) only.

2. Container open :

   • you don’ t need to specify the container format at open of an existing container. The program finds itself the container format. However, if you specify the format, it must be the real format of the container otherwise the OPEN-ZIP-CONTAINER statement is rejected. Once, the container is opened, you can add or extract files.

The following table summarizes the default behavior of the BS2ZIP application for the different file types according to the container open format:

ZIP Format	File Access
	SAM		ISAM		PAM/PLAM
WINZIP compatible	A:	Data only are saved WIN-ANSI conversion if file is EBCDIC encoded; CRLF (0D0A) are inserted as record delimiters	A:	Data and keys are saved  WIN-ANSI conversion if file is EBCDIC encoded; CRLF (0D0A) are inserted as record delimiters	A:	Binary save without any conversion
	X:	Files are extracted with same organization than the original file. EBCDIC conversion if necessary Record rebuild according to 0D0A delimiter Default processing if no organization info is associated to the file	X:	Files are extracted with same organization than the original file. EBCDIC conversion if necessary Record rebuild according to 0D0A delimiter	X:	Files are extracted with same organization than the original file. Binary rebuild
BS2000	A:	Record length saved with data No conversion	A:	Record length saved with data No conversion	A:	Binary save
	X:	Files are extracted with same organization than the original file. No conversion	X:	Files are extracted with same organization than the original file. No conversion	X:	Files are extracted with same organization than the original file. Binary rebuild

A: Add
X: Extract

Using the ADD-FILE and EXTRACT-FILE statements you can modify this default behavior. See those statements for details.

Note
In the case of a WinZip-compatible container it is assumed that a CRLF (0D0A) indicates the end of a data record. The original file may not contain any such binary values, otherwise the file is “spoilt” when it is extracted. A WinZip-compatible container should not contain any non-printable SAM or ISAM files.

ADD-FILE

CHARACTER CONVERSION	Meaning
*BY-CONTAINER-FORMAT	Default value. Behavior determined by the ZIP container open format
*NO	No conversion is forced
*TO-EBCDIC	EBCDIC conversion is forced (only for SAM/ISAM files in ASCII encoding)
*TO-WIN-ANSI	WIN-ANSI conversion is forced (only for SAM/ISAM files in EBCDIC encoding)

EXTRACT-FILE

The open format determined by ZIP container format can be modified at EXTRACT-FILE time:

DATA-TYPE	Container format
	WINZIP-COMPATIBLE	BS2000
*NOT-SPECIFIED	If no file info found in ZIP container Then *CHARACTER is assumed Else file info is used - EBCDIC conversion done according to file type	If no file info found Then error Else file info is used - no conversion
*CHARACTER	File is extracted as a SAM file Records are assumed to be delimited by 0D0A EBCDIC conversion performed	Statement rejected
*BINARY	File is extracted as a PAM file No conversion performed	Statement rejected
*SAM-BINARY	File is extracted as a SAM file, REC-FORM=U No conversion performed	Statement rejected

CHARACTER- CONVERSION	Meaning
*BY-CONTAINER-FORMAT	Default value. Behavior determined by the ZIP container open format
*NO	No conversion is forced
TO-WIN-ANSI	WIN-ANSI conversion is forced (only for extraction to SAM/ISAM file)
*TO-EBCDIC	EBCDIC conversion is forced (only for extraction to SAM/ISAM file)
*BY-PARAMETERS(...)	Conversion will be made according to specified source and target character sets (only for extraction to SAM/ISAM file)
*FROM-CCS	Origin coded character set, from which all characters will be converted. Supported coded character sets: WCP1252P, UTF8, ISO88591, ISO8859F (XHCS names, see manual XHCS [5] )
*TO-CCS	Target coded character set, to which all characters will be converted. Supported coded character sets: EDF04F, EDF041, EDF03DRV, EDF03IRV, EDF04DRV, EDF04IRV (XHCS names, see manual XHCS [5])

Block format when extracting to various disk formats

When extracting a file, BS2ZIP takes into account the disk format in which the file is stored, the block format (BLOCK-CONTROL-INFO) of the original file which is stored in the archive, and the specification in the BLOCK-CONTROL-INFO operand which controls whether the block format must be retained. As a result of this, in some cases the file cannot be extracted, or a block format which differs from that of the original file must be selected.

Extracting to K disks

The extracted files contain the block format of the original file.

Extracting to NK2 disks

Files with the PAMKEY block format cannot be extracted using the BLOCK-CONTROL= *KEEP option.

Depending on the archive format, the BLOCK-CONTROL=*IGNORE option is used to set the block format as follows:

Properties of the original file		Specification in the BLOCK-CONTROL operand
		(BS2000 format)		(WINZIP-COMPATIBLE format)
FCB type	BLK-CTRL	*KEEP	*IGNORE	*KEEP	*IGNORE
PAM	PAMKEY	Not extracted	NO	Not extracted	NO
PAM	DATA	Like original	Like original	Like original	Like original
PAM	NO	Like original	Like original	Like original	Like original
SAM	PAMKEY	Not extracted	DATA	Not extracted	DATA
SAM	DATA	Like original	Like original	Like original	Like original
ISAM	PAMKEY	Not extracted	DATA2K	Not extracted	DATA2K
ISAM	DATA	Like original	Like original	Like original	Like original