All
Enclosed are the minutes from yesterdays meeting
regards
Andrew
----
Minutes of the 6th July 2017 Teleconference Austin-825 Page 1 of 1
Submitted by Andrew Josey, The Open Group. 7th July 2017
Attendees:
Don Cragun, IEEE PASC OR
Nick Stoughton, USENIX, ISO/IEC JTC 1/SC 22 OR
Geoff Clare, The Open Group
Joerg Schilling, FOKUS Fraunhofer
David Clissold, IBM
Eric Blake, Red Hat
Andrew Josey, The Open Group
Apologies:
Richard Hansen, Google
Mark Ziegast, SHware Systems
Martin Rehak, Oracle, The Open Group OR
* General news
Andrew has submitted the draft for IEEE editorial coordination.
A pdf preview is available in the SVN repository:
https://svn.opengroup.org/websvn/listing.php?repname=POSIX&path=%2FBaseI7%2F2017+Rollup%2F
* Outstanding actions
( Please note that this section has been flushed to shorten the minutes -
to locate the previous set of outstanding actions, look to the minutes
from 28 Jan 2016)
Bug 0000249: Add standard support for $'...' in shell Reopened
http://austingroupbugs.net/bug_view_page.php?bug_id=249
We will return to bug 249 on a future call.
Bug 0000953: Alias expansion is under-specified Was Accepted as Marked
http://austingroupbugs.net/view.php?id=953
Richard has an action to propose new wording to discuss in a future telecon.
* Current Business
Bug 1045 had a comment during its interpretation review.
We believe the current resolution is OK. A new bug report covering
the problem mentioned may be reported and resolved at a later date.
Andrew took an action to approve the interpretation - completed
after the meeting.
Bug 1041: Encourage implementations to include better integrity checksum,
compression and decompression utilities if possible. OPEN
http://austingroupbugs.net/view.php?id=1041
The bug has its own page in the etherpad:
http://posix.rhansen.org:9001/p/bug1041
We will pick up on this next week.
Bug 1053: Add a "size" mode to stty(1) OPEN
http://austingroupbugs.net/view.php?id=1053
This remains open.
Bug 1054: stdio.h doesn't allow FILE to be opaque? Accept as Marked
http://austingroupbugs.net/bug_view_page.php?bug_id=1054
This item is tagged for Issue 8
Make the change suggested in the Desired Action and also add new
paragraph in the <stdio.h> Application Usage section after P357,
L12184:
Since the latest revision of the C Standard allows FILE to be
an incomplete type (and POSIX also allows it), portable
applications can no longer allocate or copy an object of type
FILE; only pointers to objects of type FILE can be allocated.
Bug 1055: unspecified how much is parsed before execution begins Accept as
Marked
http://austingroupbugs.net/bug_view_page.php?bug_id=1055
This item is tagged for Issue 8
On page 2322 after line 73689 (just before XCU 2.3.1 Alias
Substitution), insert a new paragraph:
Once a complete_command symbol has been recognized by the grammar
(see [xref to 2.10 Shell Grammar]), the complete_command shall
be subjected to alias substitution (see [xref to 2.3.1 Alias
Substitution]) then executed before the next complete_command
is tokenized and parsed.
On page 2322 lines 73691-73693 (XCU 2.3.1 Alias Substitution), change:
After a token has been delimited, but before applying the
grammatical rules in Section 2.10, a resulting word that is
identified to be the command name word of a simple command shall
be examined to determine whether it is an unquoted, valid alias
name.
to:
After a sequeunce of tokens has been parsed and recognized as
a command or compound list by the grammar (see [xref to 2.10
Shell Grammar]), but before the command or compound list is
executed, each word that is identified to be the command name
word of a simple command shall be examined to determine whether
it is an unquoted, valid alias name.
On page 2331 line 74073 (XCU 2.6.3 Command Substitution), add a new
sentence at the end of the paragraph at lines 74067-74073:
After backslashes have been processed, the characters in command
shall be tokenized (see [xref to XCU 2.3 Token Recognition]),
then parsed as a single compound_list (see [xref to XCU 2.10
Shell Grammar]), then subjected to alias substitution (see [xref
to 2.3.1]), then executed.
On page 2331 line 74076 (XCU 2.6.3 Command Substitution), add a new
sentence at the end of the paragraph at lines 74074-74076:
The characters in command shall be tokenized (see [xref to XCU
2.3 Token Recognition]), then parsed as a single compound_list
(see [xref to XCU 2.10 Shell Grammar]), then subjected to alias
substitution (see [xref to 2.3.1]), then executed.
On page 2325 lines 73782-73785 (XCU 2.5.3 Shell Variables, ENV) change:
This variable, when and only when an interactive shell is
invoked, shall be subjected to parameter expansion (see Section
2.6.2) by the shell and the resulting value shall be used as a
pathname of a file containing shell commands to execute in the
current environment.
to:
This variable, when and only when an interactive shell is
invoked, shall be subjected to parameter expansion (see Section
2.6.2) by the shell and the resulting value shall be used as a
pathname of a file. Before any interactive commands are read,
the contents of the file shall be tokenized, parsed, subjected
to alias expansion, and executed as described in [xref to 2.3
Token Recognition]. The contents shall be executed in the current
environment.
On page 2364 line 75304 (XCU 2.14 dot DESCRIPTION), change:
The shell shall execute commands from the file in the current environment.
to:
The contents of file shall be tokenized (see [xref to XCU 2.3
Token Recognition]), then parsed as a single compound_list (see
[xref to XCU 2.10 Shell Grammar]), then subjected to alias
substitution (see [xref to 2.3.1]), then executed in the current
environment.
On page 2366 line 75371 (XCU 2.14 eval), change:
The constructed command shall be read and executed by the shell.
to:
The constructed command shall be tokenized (see [xref to XCU
2.3 Token Recognition]), then parsed as a single compound_list
(see [xref to XCU 2.10 Shell Grammar]), then subjected to alias
substitution (see [xref to 2.3.1]), then executed in the current
environment.
On page 2350 after line 74800 (XCU 2.10.2 Shell Grammar Rules), insert the
following comment above %start:
/* The start symbol is compound_list when parsing dot scripts, command
substitution bodies, and the arguments passed to eval */
On page 3678 after line 125707 (just before XRAT C.2.3.1), insert
a new paragraph:
Because a complete_command is executed before the next
complete_command is tokenized and parsed, syntax errors are not
discovered by the shell until just before the code would be
executed. While in some cases it might be desirable to detect
and react to syntax errors before anything is executed, deferring
the discovery of syntax errors has several benefits:
It makes it possible for script authors to test for the
avilability of a nonstandard extension and react appropriately
before the use of the extension would trigger a syntax
error.
It makes it possible to create self-extracting tarballs (a
shell script concatenated with a payload archive that
extracts the archive when executed).
The shell does not have to read and parse the complete
script before execution, which reduces memory usage when
executing extremely long scripts.
On page 3681 lines 125831-125832 (XRAT C.2.5.3 ENV) change:
However, unlike dot scripts, no PATH searching is performed.
This is used as a guard against Trojan Horse security breaches.
to:
However, unlike dot scripts, ENV scripts are parsed as a program,
not a compound_list. This distinction matters because it
influences when aliases take effect and whether syntax errors
in the script are discovered before any part of the script is
executed.
For security reasons, PATH is not searched when locating the ENV script.
Bug 1056: CMSG_NXTHDR(): under what criteria may NULL be returned? OPEN
http://austingroupbugs.net/bug_view_page.php?bug_id=1056
This item will be discussed next time
Next Steps
----------
The next call is on July 13th, 2017 (a Thursday)
Calls are anchored on US time. (8am Pacific)
This call will be for the regular 90 minutes.
http://austingroupbugs.net
An IRC channel will be available for the meeting
irc://irc.freenode.net/austingroupbugs
An etherpad is usually up for the meeting, with a URL using the date format as
below:
https://po...@posix.rhansen.org/p/201x-mm-dd
password=2115756#
--------
Andrew Josey The Open Group
Austin Group Chair
Email: a.jo...@opengroup.org
Apex Plaza, Forbury Road,Reading,Berks.RG1 1AX,England
Tel:+44 118 9023044
I’m Giving Back at the London Half Marathon Walk Sep 23rd 2017
https://www.justgiving.com/teams/openforkids
