Randy Medd ([log in to unmask]) wrote:
: Take care with this last part.  I did the following:
 
:   :BUILD OLDFILE;REC=-80,,F,ASCII
:   :LN.HPBIN.SYS "-s ./OLDFILE ./NEWFILE"
:   :LISTF ???FILE,2
:   ACCOUNT=  TELAMON     GROUP=  RANDY
 
:   FILENAME  CODE  ------------LOGICAL RECORD-----------  ----SPACE----
:                     SIZE  TYP        EOF      LIMIT R/B  SECTORS #X MX
 
:   NEWFILE             1B  BAL          9       1024   1       16  1  *
:   OLDFILE            80B  FA           0       1023   3        0  0  *
 
:   :PURGE NEWFILE
:   :LISTF ???FILE,2
:   ACCOUNT=  TELAMON     GROUP=  RANDY
 
:   FILENAME  CODE  ------------LOGICAL RECORD-----------  ----SPACE----
:                     SIZE  TYP        EOF      LIMIT R/B  SECTORS #X MX
 
:   NEWFILE             1B  BAL          9       1024   1       16  1  *
 
:   :LS.HPBIN.SYS "-l ./NEWFILE"
:   lrwxrwxrwx   1 MANAGER.SYS TELAMON 9 May 23 13:43 ./NEWFILE -> ./OLDFILE
:   :
 
: Notice that the PURGE deleted _OLDFILE_, not NEWFILE, although the
: link of NEWFILE -> OLDFILE still remained.  If you build a link using
: LN.HPBIN.SYS, you'll have to get rid of it using RM.HPBIN.SYS, _not_
: PURGE.
 
This is a distinction between PURGE and PURGELINK in the CI, and is an
important concept for MPE users to understand.  If you :PURGE a link, it
is like saying :PURGE *FILE, where FILE references a previous file equation.
The file on the right side of the file equation will be purged.
 
If you want to get rid of the link, use :PURGELINK NEWFILE in the CI.
 
At the 1994 Interex in Denver, I did a paper called "A System Manager's Look
at MPE/iX 5.0", which covered some MPE/POSIX topics like this.  I tried to
explain POSIX things in MPE/iX terms.  I wrote it for someone who is trying
to understand POSIX-style concepts from an MPE/iX knowledge base.  It is
paper #8008 in the proceedings from that conference.
 
Kevin Cooper
HP Commercial Systems Division