Look at the CHECKSUM or CIPHER MESSAGE instructions it might do what you want too.
Mark Jacobs Sent from ProtonMail, Swiss-based encrypted email. GPG Public Key - https://api.protonmail.ch/pks/lookup?op=get&[email protected] On Saturday, February 7th, 2026 at 7:10 PM, Farley, Peter <[email protected]> wrote: > Cross posted to CICS-L and IBM-MAIN. > > I have a POC that will require me to compute a simple SHA-1 hash of a text > value less than 64 bytes long to create a 20-byte value that is unique enough > for purposes of the POC. As far as I can tell so far, more complex hashes are > not needed for the expected text values. In my testing so far, the first 10 > bytes of the SHA-1 value turn out to be unique enough. > > The ICSF callable service CSNBOWH is what I am using to compute the SHA-1 > value, and the batch testing I have done so far shows acceptable performance > and 100% uniqueness for purposes of the POC. > > The hash function will be invoked fairly frequently, at least multiple times > (probably less than 20 though) in a single CICS transaction or batch record > process. > > My question is whether it safe to directly call CSNBOWH in a CICS application > (dynamic CALL, not CICS LINK) that is running in the QR task? The SHA-1 > function of CSNBOWH is documented as only requiring CPACF hardware so I have > been ASSUMING that calling this service will not cause a wait in the QR task, > but I felt it would be better to ask the assembled expertise on these lists. > > Alternatively, is there a CICS function or command that I should use instead > of calling CSNBOWH to compute a SHA-1 hash? > > Peter > > > This message and any attachments are intended only for the use of the > addressee and may contain information that is privileged and confidential. If > the reader of the message is not the intended recipient or an authorized > representative of the intended recipient, you are hereby notified that any > dissemination of this communication is strictly prohibited. If you have > received this communication in error, please notify us immediately by e-mail > and delete the message and any attachments from your system. > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
