On Fri, 15 Feb 2008 09:05:59 EST, IBM Mainframe Discussion List wrote: > >The reason that a PDS directory entry that describes a load module is larger >than a directory entry for other types of data is that load modules store >info in the entry that is used by program fetch when the load module is being >loaded.
It's called the user data field. ISPF also uses it >I don't remember the exact format of a directory entry, but there is >at least one TTR stored in the entry as well as part of a byte telling how >many halfwords of the directory entry are used for storing such data. Yes. 5 bits, allowing for up to 31 halfwords. >Non-load modules have all these bytes containing zero. ITYM bits. Members with no user data. This is what defines the length of the entry. 12 bytes plus as many halfwords as specified >Some non-IBM products use >this feature of a directory entry to store useful info, like date last used >for >the member. So non-load module entries will be larger than the mininum >length (12 bytes, I think) if such software is installed and managing that PDS. >There is a DSECT describing the directory entry somewhere in >SYS1.MACLIB/MODGEN, I believe. IHAPDS -- Tom Marchant ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
