i have a requirement to check for the member name in some PDS, but the PDS has more than 65000 members so it will take good amount of time if i wanted to do it in rexx. i am just thinking of any other functions in rexx which gives me some kind of information whether the member is present or not when i pass PDS NAME and MEM NAME to that.
I thought of getting the member list in an array for the particular PDS using LISTDS MEMBER command. It will take good amount of time if i check for the member name whether it is present in the array or not.
If you can, read the directory once into a stem variable rather than reading the directory multiple times. You can use LISTDS, IEHLIST, ISPF, or read the directory directly with Rexx. All are pretty fast if you are only doing it once. Reading a 65000 member directory to a stem variable with EXECIO took 2.6 seconds on my system but ISPF services should faster