Peter, thanks much, you are always so helpful. Very similar to SNA SCS.
I am going to guess "... with the block being prefixed by a single x'80' indicating 'this data is CSRCESRV compressed.'" That's what threw me off in my half-hearted attempts to "decode" the scheme. This is helpful -- knowing that (for now at least) the longest possible run will be 127 bytes. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Peter Relson Sent: Thursday, June 13, 2013 6:31 AM To: [email protected] Subject: Re: anyone familiar with how z/OS CSRCESRV works? Apologies if this is a duplicate post; I sent this a couple of days ago but never saw it in the digest. Note that this is not an interface, nor a commitment that it will stay this way forever; there is no current activity that would lead one to think a change is forthcoming. This is from the module: Each run is composed of a Substring Control Byte (SCB) followed by 1 to 127 text bytes. For non-repeat runs, the SCB contains a count of the number of text bytes that follow, with a high order bit of '0'B, followed by that number of bytes of text ------------------------------------- ---------- |0 n | byte 1 | byte 2 | byte 3 | .... | byte n | ------------------------------------- ---------- Where n is the number of non-repeat bytes in the run. For repeat runs, the SCB contains a count of the number of repeated bytes th string represents, with a high order bit of '1'B, followed by a single copy of the repeat byte. ------------------- |1 n | byte 1 | ------------------- Where n is the number of repeat bytes in the run. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
