AddResidentPrg(33.4)     ARP Prog Manual	  AddResidentPrg(33.4)



     NAME
	  AddResidentPrg -- Add	a program to the resident list.

     SYNOPSIS
	  node = AddResidentPrg(segment, name)
	    d0			  d1	  a0

     FUNCTION
	  ARP's	Resident Program manager is a sort of software MMU
	  that attempts	to allow programs to run multiple times	with
	  only one copy	of their code in memory. The result is similar
	  to Unix(tm) shared text processes.  Provisions have been
	  made to allocate extra data segments for programs that are
	  not reentrant, these are allocated automatically if the
	  program begins with a	ResidentProgramTag and is also on the
	  resident list.  Additionally,	the ResidentProgramTag stores
	  a min	stacksize needed to run	the program, this is used and
	  overrides all	user stack requests whether or not the program
	  is on	the Resident list.

	  A program does not need to have a ResidentProgramTag to be
	  installed on the resident list.  Programs are	checksummed
	  upon being added, and	checked	each time they are obtained.
	  While	not perfect, this provides a reasonable	method of
	  weeding out most non-resident	programs.  As a	general	guide,
	  all ARP programs currently will run as resident programs.
	  Most current C programs modify their data, and so cannot be
	  run without using the	ResidentProgramTag to allocate and
	  copy data.  Programs which write into	their own code
	  segments, such as those which	do SegList splits, will	never
	  run as Resident, and will likely never run under a hardware
	  MMU either.  Some programs, such as MicroSmith's TxED, check
	  to see if they are on	the ResidentList before	doing a
	  seglist split.  These	should be ok as	resident.

	  All names on the resident list are stored using their
	  BaseName's only.  Matches will succeed if you	specify	a full
	  pathname, but	the match only examines	the basename of	each.

	  This list is protected using a signal	semaphore in ArpBase,
	  so the overall impact	on the system for searches is very
	  low.	Generally, you will not	need to	obtain this semaphore
	  for yourself,	since all these	functions (except
	  CheckSumPrg()) handle	the locking of the list	for you.  In
	  general, these functions do not need to be called, you
	  should usually use the higher	level LoadPrg()	UnLoadPrg()
	  functions instead.

     INPUTS
	  segment - BPTR as returned by	LoadSeg().

	  name - pointer to a null terminated pathname.	 This may be



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     AddResidentPrg(33.4)     ARP Prog Manual	  AddResidentPrg(33.4)



		  any valid AmigaDOS pathname, but only	the BaseName
		  of the path is compared and stored. Note that	the
		  resident name	does not need to be the	same as	the
		  original diskfile name.

     RESULT
	  node - If found, a pointer to	the resident program node for
		  the program.	If NULL, it could not be added.	Note
		  that it is impossible	to add the same	name twice to
		  the resident list.  On failure, more information is
		  available by calling IoErr().

     BUGS
	  None known

     SEE ALSO
	  ObtainResidentPrg(), RemResidentPrg(), LoadPrg(),
	  UnLoadPrg(), CheckSumPrg(), ReleaseResidentPrg(),
	  BaseName().

     AUTHOR
	  SDB

































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