<snip> I assume that the potential exposure in case 1 when adding as opposed to replacing a program is that the directory is in a state of flux involving moving entries from one block to the next (a replace would usually only rewrite a single block up update the TTR). I know that there is an EXC ENQ on a special Linkedit QNAME to serialize the updates but that only locks access to other linkedit/bind tasks). </snip>
All three of the OP's scenarios involve the update of a PDS/Directory while the information in that PDS/Directory is in a state of flux. The enqueues/dequeues involved are designed to serialize the access so that a "state of flux" is not possible for the duration of the update. All of the OP's scenarios had solutions. All of those solutions had risk. Risk can be mitigated or accepted by those with appropriate knowledge. This kind of knowledge generally comes from experience. Us old-timers need to educate the youngsters! ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
