From:	CSBVAX::MRGATE!Info-VAX-RELAY@KL.SRI.COM@SMTP  6-FEB-1988 21:14
To:	ARISIA::EVERHART
Subj:	What's in Process-Permanent names READ/NEWRe: Translating logical names from C


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Date:    Sat, 30 Jan 88 10:42:51 PST
From:     nagy%warner.hepnet@LBL.Gov (Frank J. Nagy, VAX Wizard & Guru)
Message-Id: <880130104251.23c00415@LBL.Gov>
Subject: What's in Process-Permanent names READ/NEWRe: Translating logical names from C
To:       Info-VAX@kl.sri.com
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> ...
> that "process-permanent" logical names (e.g, SYS$INPUT) have a 4-byte
> booger prepended to their translations. ...
> ... (Anybody know what that 4 bytes of stuff is?)
     
As I remember it, the 4 bytes contain:

	- the ESC character ( 33 hex) which indicates the logical name
	  contains this binary information in addition to the text
	- a pad of 00 (NUL character)
	- a 16-bit RMS ISI (Internal Stream Identifier) of the permanently
	  opened Process Permanent File  <<hmm, or this might be the
	  IFI - Internal File Identifier>>

The ISI is used when a program does an OPEN on this logical name to connect
the RAB associated with that OPEN to the already OPEN file.  Note that
RMS turns your FABs and RABs into internal control blocks located by the
IFIs and ISIs.


= Frank J. Nagy   "VAX Guru & Wizard"
= Fermilab Research Division EED/Controls
= HEPNET: WARNER::NAGY (43198::NAGY) or FNAL::NAGY (43009::NAGY)
= BitNet: NAGY@FNAL
= USnail: Fermilab POB 500 MS/220 Batavia, IL 60510

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