View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0000265 | 1003.1(2004)/Issue 6 | Shell and Utilities | public | 2010-06-25 16:08 | 2013-04-16 13:06 |
| Reporter | geoffclare | Assigned To | ajosey | ||
| Priority | normal | Severity | Objection | Type | Clarification Requested |
| Status | Closed | Resolution | Accepted | ||
| Name | Geoff Clare | ||||
| Organization | The Open Group | ||||
| User Reference | |||||
| Section | more | ||||
| Page Number | 643 | ||||
| Line Number | 24934-24941 | ||||
| Interp Status | Approved | ||||
| Final Accepted Text | 0000265:0000440 | ||||
| Summary | 0000265: more -e contradiction | ||||
| Description | The specification of the more utility contains a contradiction with regard to the -e option. The description of the -e option is: By default, more shall exit immediately after writing the last line of the last file in the argument list. If the -e option is specified: 1. If there is only a single file in the argument list and that file was completely displayed on a single screen, more shall exit immediately after writing the last line of that file. 2. Otherwise, more shall exit only after reaching end-of-file on the last file in the argument list twice without an intervening operation. See the EXTENDED DESCRIPTION section. However, the EXTENDED DESCRIPTION states: For all files but the last (including standard input if no file was specified, and for the last file as well, if the -e option was not specified), when more has written the last line in the file, more shall prompt for a user command. Both pieces of text are from POSIX.2b. It appears that the intention in .2b was to change the requirements for -e and the default end-of-last-file behaviour to the opposite of what POSIX.2-1992 required (except in the case of a single file completely displayed on a single screen), but the need to remove the word "not" from the above parenthetical statement in the extended description was overlooked. However, given that the standard has, since 2001, contradicted itself, we have an opportunity to revisit the .2b decision. In particular, all currently certified UNIX03, UNIX98 and UNIX95 systems still behave as per the original POSIX.2-1992 requirement. They have not followed the intended .2b change. The original POSIX.2-1992 requirement makes more sense to me, given that the ability to scroll backwards was added to the more utility by POSIX.2. I think most users on reaching the end of the last file would want the choice of scrolling back or exiting, so prompting _should_ be the default (except perhaps in the case of a single file completely displayed on a single screen). Therefore I propose that we reinstate the POSIX.2-1992 requirement at the next opportunity (TC1 of the 2008 revision), so that the standard once again matches existing practice, and the edits suggested below do that. The .2b requirement relating to a single file completely displayed on a single screen could also be retained if desired, although it would have to move from the -e description to the extended description. An alternative solution would be to specify two options (such as -e and -E), one which selects exit-at-end-of-last-file and one which selects prompt-at-end-of-last-file, and say that it is unspecified which one is the default, and that "the last one wins". This would allow users to include their preferred option in an alias and/or the PAGER variable, and to override it on occasion if necessary. | ||||
| Desired Action | Replace the description of the -e option with: Exit immediately after writing the last line of the last file in the argument list; see the EXTENDED DESCRIPTION section. | ||||
| Tags | tc1-2008 | ||||
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Copied from xcubug2.txt ERN 185 |
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Interpretation response ------------------------ The standard is unclear on this issue, and no conformance distinction can be made between alternative implementations based on this. This is being referred to the sponsor. Rationale: ------------- None. Notes to the Editor (not part of this interpretation): ------------------------------------------------------- Make the change suggested by the submitter. (In the 2008 edition std p2943 lines 96840-96845) |
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Comments/objections on the proposed interpretation are due by COB Aug 31 2010 |
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We believe that this change makes the standard match historic practice. Therefore, this change is suitable for a TC and need not wait for the next revision of the standard. |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2010-06-25 16:08 | geoffclare | New Issue | |
| 2010-06-25 16:08 | geoffclare | Status | New => Under Review |
| 2010-06-25 16:08 | geoffclare | Assigned To | => ajosey |
| 2010-06-25 16:08 | geoffclare | Name | => Geoff Clare |
| 2010-06-25 16:08 | geoffclare | Organization | => The Open Group |
| 2010-06-25 16:08 | geoffclare | Section | => more |
| 2010-06-25 16:08 | geoffclare | Page Number | => 643 |
| 2010-06-25 16:08 | geoffclare | Line Number | => 24934-24941 |
| 2010-06-25 16:08 | geoffclare | Interp Status | => --- |
| 2010-06-25 16:08 | geoffclare | Note Added: 0000435 | |
| 2010-06-25 16:09 | geoffclare | Note Edited: 0000435 | |
| 2010-06-26 17:40 | geoffclare | Note Added: 0000440 | |
| 2010-06-26 17:41 | geoffclare | Interp Status | --- => Pending |
| 2010-06-26 17:41 | geoffclare | Final Accepted Text | => 0000265:0000440 |
| 2010-06-26 17:41 | geoffclare | Status | Under Review => Interpretation Required |
| 2010-06-26 17:41 | geoffclare | Resolution | Open => Accepted |
| 2010-07-30 08:18 | ajosey | Interp Status | Pending => Proposed |
| 2010-07-30 08:18 | ajosey | Note Added: 0000491 | |
| 2010-09-03 16:37 | ajosey | Interp Status | Proposed => Approved |
| 2010-09-09 15:21 | Don Cragun | Tag Attached: tc1-2008 | |
| 2010-09-09 15:23 | Don Cragun | Note Added: 0000543 | |
| 2013-04-16 13:06 | ajosey | Status | Interpretation Required => Closed |
