From owner-ntemacs-users@june Mon Sep 23 08:16:46 1996 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil "Mon" "23" "September" "1996" "10:26:28" "-0400" "Kenneth L. Degrant, II" "kdegrant@earthlink.net" nil "28" "19.34 and Shell" "^From:" nil nil "9" nil nil nil nil] nil) Received: from joker.cs.washington.edu (joker.cs.washington.edu [128.95.1.42]) by june.cs.washington.edu (8.7.5/7.2ju) with SMTP id IAA26377 for ; Mon, 23 Sep 1996 08:16:46 -0700 Received: from june.cs.washington.edu (june.cs.washington.edu [128.95.1.4]) by joker.cs.washington.edu (8.6.12/7.2ws+) with ESMTP id IAA23335 for ; Mon, 23 Sep 1996 08:16:45 -0700 Received: from hungary.it.earthlink.net (hungary-c.it.earthlink.net [204.119.177.64]) by june.cs.washington.edu (8.7.5/7.2ju) with ESMTP id HAA24655 for ; Mon, 23 Sep 1996 07:23:20 -0700 Received: from a12051.dracon.harris.com (a12051.nss.harris.com [151.114.22.138]) by hungary.it.earthlink.net (8.7.5/8.7.3) with SMTP id HAA13407 for ; Mon, 23 Sep 1996 07:23:15 -0700 (PDT) Message-ID: <32469E14.2D4@earthlink.net> Organization: Harris Corporation X-Mailer: Mozilla 2.01 (Win95; I) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: "Kenneth L. Degrant II" To: ntemacs-users@cs.washington.edu Subject: 19.34 and Shell Date: Mon, 23 Sep 1996 10:26:28 -0400 When I went from 19.33 to 19.34, I started having problems spawning grep, or compile, with "start-process-shell-command" I gave it the name of a bat file which prints the args, and I got argv0 = mybat.bat one two three four...... argv1 = argv..... What am I doing wrong, or what is wrong. For now I am going to go back to 19.33. Kenneth -- ------------------------------------------------------------------------------ Kenneth L. DeGrant II E-Mail: kdegrant@earthlink.net Software Engineer kdegrant@harris.com Harris Corporation Phone: (910) 856-5445 Greensboro Operations Fax: (910) 852-1820 3708 Alliance Drive Greensboro, North Carolina 27407 http://home.earthlink.net/~kdegrant ------------------------------------------------------------------------------ From andrewi@harlequin.co.uk Fri Jul 26 07:56:59 1996 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil "Fri" "26" "July" "1996" "15:55:29" "+0100" "Andrew Innes" "andrewi@harlequin.co.uk" nil "96" "Re: [preilly@rokchr.shr.dec.com: VC checkin failure]" "^From:" nil nil "7" nil nil nil nil] nil) Received: from holly.cam.harlequin.co.uk (holly.cam.harlequin.co.uk [193.128.4.58]) by june.cs.washington.edu (8.7.5/7.2ju) with SMTP id HAA08360 for ; Fri, 26 Jul 1996 07:56:57 -0700 Received: from propos.long.harlequin.co.uk by holly.cam.harlequin.co.uk; Fri, 26 Jul 1996 15:56:54 +0100 Received: from woozle.long.harlequin.co.uk (woozle [193.128.93.77]) by propos.long.harlequin.co.uk (8.6.12/8.6.12) with SMTP id PAA23293; Fri, 26 Jul 1996 15:55:29 +0100 Message-Id: <199607261455.PAA23293@propos.long.harlequin.co.uk> In-Reply-To: <199607260454.VAA39246@joker.cs.washington.edu> (voelker@cs.washington.edu) From: Andrew Innes To: voelker@cs.washington.edu Cc: rms@gnu.ai.mit.edu Subject: Re: [preilly@rokchr.shr.dec.com: VC checkin failure] Date: Fri, 26 Jul 1996 15:55:29 +0100 On Thu, 25 Jul 1996 21:02:27 -0700 (PDT), voelker@cs.washington.edu (Geoff Voelker) said: >The short story then is that sometimes we want arguments quoted (when >they truly are arguments with whitespace in them) and at other times >we don't (when they are entire commands and arguments concatenated >together into one string but separated by whitespace), and it is not >obvious how to distinguish these cases inside Emacs. If arguments to >commands were always broken up into argv components by the time it >reaches child_setup (e.g., the grep command, even though an argument >to the shell, would be broken up into its components, too), then I >think we could safely set win32-quote-process-args to t by default. >But this seems impossible to ensure. Thinking about it from the Unix perspective, the argv array given to child_setup is already correct because the shell expects a single arg containing the entire command following -c, which it will interpret as if it was typed in at the command line and so construct the proper argv array for grep. If the standard shell on NT had a sufficiently powerful quoting and escaping syntax, as the Unix shells do, then this would work on NT as well even though we have to flatten the array into a single string - any quoting in the original command arg could be passed through to the shell by proper escaping. As it is now, for shell commands the correct behaviour is to have win32-quote-process-args turned off, because cmd.exe will interpret the rest of its command line (after consuming things it believes are command switches for it) as a command line typed by the user. (When using a different shell, though, the rule might well be different.) When starting other processes directly, usually the right thing is to have win32-quote-process-args enabled - we have to assume that the caller has constructed the argv array as they intend the subprocess to see it (if they haven't, then things would fail on Unix), so in this case, Emacs should quote the args as necessary to ensure the subprocess reconstructs the args as intended. In general this isn't possible because there is no standard or universally used convention for parsing the command line, but most of the time putting double quotes around an arg if it contains spaces is correct. It would have been nice if all places in lisp code which run commmands via a shell process used shell-command or shell-command-on-region (so we could set win32-quote-process-args there), but a quick perusal of the lisp dir shows lots of examples where code does (call-process shell-file-name ... "-c" args) or similar things. It is too much to expect all packages to go through the shell-command interface, so we need to deal with this at a lower level than shell-command. [One possibility: If we could insist that people use a specific shell on NT (not cmd.exe), then we could solve the shell command problem that way. Or more likely, we would provide a subprocess "helper" application that NT Emacs always used to invoke whatever program is really intended. This ends up using extra process resources unnecessarily in many cases.] >Alternatively, we could have the NT specific code check to see if the >command it is spawning is the shell (and the second argument is the >equivalent of "/c"), and have that code automatically break up into >components the command to be executed in the shell (assuming that >words that should go together are already quoted). Otherwise, we >would quote any arguments with whitespace in them (that are not >already quoted). Andrew, can you think of a case where this wouldn't >work very well? No - I think something along these lines will be necessary (and this is the best suggestion I've seen so far). However, it occurs to me that we should really provide a way for the user to specify what kind of quoting behaviour is required in each case. We know that the correct quoting really depends on which shell program is being used (and not just shells - some individual programs may require special handling as well). I suggest adding a hook or handler mechansim of some sort (to both start-process and call-process) to allow lisp code to modify the arg list before it is passed to child_setup. That way, the lisp code could implement proper quoting, or splitting of args etc, based on the program name or whatever criteria was considered appropriate. This would even allow working with packages that directly call "sh", "rm", or other Unix-specific programs - if a user wanted to, they could intercept invocations of specific programs and invoke an appropriate substitute instead. In the case of call-process, they might even want to implement the functionality entirely in lisp (eg. you could imagine ls-lisp working this way), but this is probably going too far. Then child_setup et al would not need to worry about this issue - win32-quote-process-args would go, and sys_spawnve would always simply concatenate the args together separated by spaces. Does this sound like a reasonable solution? AndrewI From andrewi@harlequin.co.uk Fri Jul 26 08:52:39 1996 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil "Fri" "26" "July" "1996" "16:52:29" "+0100" "Andrew Innes" "andrewi@harlequin.co.uk" nil "27" "Re: [preilly@rokchr.shr.dec.com: VC checkin failure]" "^From:" nil nil "7" nil nil nil nil] nil) Received: from holly.cam.harlequin.co.uk (holly.cam.harlequin.co.uk [193.128.4.58]) by june.cs.washington.edu (8.7.5/7.2ju) with SMTP id IAA13939 for ; Fri, 26 Jul 1996 08:52:37 -0700 Received: from propos.long.harlequin.co.uk by holly.cam.harlequin.co.uk; Fri, 26 Jul 1996 16:52:34 +0100 Received: from woozle.long.harlequin.co.uk (woozle [193.128.93.77]) by propos.long.harlequin.co.uk (8.6.12/8.6.12) with SMTP id QAA26541; Fri, 26 Jul 1996 16:52:29 +0100 Message-Id: <199607261552.QAA26541@propos.long.harlequin.co.uk> In-Reply-To: <199607261455.PAA23293@propos.long.harlequin.co.uk> (andrewi) From: Andrew Innes To: andrewi@harlequin.co.uk Cc: voelker@cs.washington.edu, rms@gnu.ai.mit.edu Subject: Re: [preilly@rokchr.shr.dec.com: VC checkin failure] Date: Fri, 26 Jul 1996 16:52:29 +0100 On Fri, 26 Jul 1996 15:55:29 +0100, Andrew Innes said: [ .. ] >However, it occurs to me that we should really provide a way for the >user to specify what kind of quoting behaviour is required in each case. >We know that the correct quoting really depends on which shell program >is being used (and not just shells - some individual programs may >require special handling as well). > >I suggest adding a hook or handler mechansim of some sort (to both >start-process and call-process) to allow lisp code to modify the arg >list before it is passed to child_setup. That way, the lisp code could >implement proper quoting, or splitting of args etc, based on the program >name or whatever criteria was considered appropriate. An obvious way of adding a "hook" mechansim would be to introduce a variable `process-name-arg-handler-alist' (say), which relates regexps (matching on program name) to handler functions that would return the actual argument list (including the program name) to be used. If the handler was `t' then "standard" quoting of args with spaces would be performed; `nil' would mean use the original arg list directly. There is no reason this mechansim (if accepted) shouldn't be provided for all platforms, although it is most useful for Windows (and DOS, and maybe VMS). AndrewI From eliz@is.elta.co.il Tue Nov 4 02:38:29 1997 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil "Tue" " 4" "November" "1997" "12:35:41" "+0200" "Eli Zaretskii" "eliz@is.elta.co.il" nil "63" "Re: win32-quote-process-args" "^From:" nil nil "11" nil nil nil nil] nil) Received: from is.elta.co.il (is.elta.co.il [199.203.121.2]) by june.cs.washington.edu (8.8.7+CS/7.2ju) with SMTP id CAA06714; Tue, 4 Nov 1997 02:38:27 -0800 Received: by is.elta.co.il (SMI-8.6/SMI-SVR4) id MAA19348; Tue, 4 Nov 1997 12:35:42 +0200 X-Sender: eliz@is In-Reply-To: <199711032109.OAA04908@airedale.ihsyp> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII From: Eli Zaretskii To: kevin.rodgers@ihs.com cc: GNU Emacs information , NT Emacs mailing list , Geoff Voelker , Andrew Innes Subject: Re: win32-quote-process-args Date: Tue, 4 Nov 1997 12:35:41 +0200 (IST) I don't maintain the NT port, and I didn't write the code that handles this, so please take the following with a grain of salt. Goeff and Andrew will have a better insight. On Mon, 3 Nov 1997, Kevin Rodgers wrote: > Can someone explain the purpose and use of the win32-quote-process-args > variable in GNU Emacs for Windows 95/NT? I maintain a package > (igrep.el) that generates shell commands with quoted arguments, and am > trying to support those inexplicably popular platforms. However, I > don't even know what the doc string for that variable says. See src/w32proc.c It has some comments about this. In a word, it's a mess. While on Unix wildcards are expanded by the shell, native W95/NT shells don't do that (I'm positive about W95, but might be in error about NT). Therefore, there are two possible situations: either the user installed a port of Unixy shell (such as Bash) or they use the stock shell. In the first case, you don't need to quote the arguments at all, since the caller (the one which is responsible for invoking the subprocess, in this case igrep.el) should have quoted whatever needs to be quoted for such a shell. It's the second case that might let all hell break lose on you. In this case, the wildcards are expanded by the application's startup code. The problem is, every compiler/library have their own ways of handling that, including how special characters are quoted. Making it all work correctly is a programmer's nightmare. > For starters, who is responsible for setting it: the Windows 95/NT Emacs > implementation itself, the user (to make sure it's compatible with > his/her setting of shell-file-name), or the programmer who calls > shell-command or shell-command-on-region or start-process-shell-command? > According to the bash, ksh, MKS ksh, and tchs items under > , > it's the user's responsibility to set it. This is correct, IMHO. The user who knows what kind of input their `grep' expects, should set this variable, if they need it (but see below). The programmer (you) don't have any clue about these; the code on w32proc.c tries to guess the correct quoting by looking at the executable, but it might easily get it wrong. In addition, if `igrep' gets the command line from the user, the best bet is for the user to quote the command line like their `grep' expects. After all, that is what they would do if they had invoked `grep' from the command line, right? > Since I am generating > a shell command with a quoted argument, it would make sense for me to > temporarily disable this "feature". But I don't understand why a user's > choice of shell should interact with this variable's value. I don't know anything about igrep, so I cannot answer this. It seems that if you quote the command line, it would be best to disable Emacs's quoting. But quoting has its pitfalls, and I cannot advise without seeing the command line. One problem that might haunt you is that most applications that expand wildcards don't know about the single quotes, only double quotes are supported. Another problem with stock Windows shells is that they will not strip quotes from the arguments when they pass them to `grep', which will then disable the globbing of wildcards by `grep's startup code. From eliz@is.elta.co.il Tue Nov 4 02:43:10 1997 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil "Tue" " 4" "November" "1997" "12:36:19" "+0200" "Eli Zaretskii" "eliz@is.elta.co.il" nil "28" "Re: Ediff cannot handle C-m in output of diff" "^From:" nil nil "11" nil nil nil nil] nil) Received: from is.elta.co.il (is.elta.co.il [199.203.121.2]) by june.cs.washington.edu (8.8.7+CS/7.2ju) with SMTP id CAA06736; Tue, 4 Nov 1997 02:39:41 -0800 Received: by is.elta.co.il (SMI-8.6/SMI-SVR4) id MAA19355; Tue, 4 Nov 1997 12:36:20 +0200 X-Sender: eliz@is In-Reply-To: <199711032106.WAA10322@aciinfo1.mchp.siemens.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII From: Eli Zaretskii To: Thorbjoern Hansen cc: bug-gnu-emacs@prep.ai.mit.edu, Michael Kifer , voelker@cs.washington.edu, ntemacs-users@cs.washington.edu Subject: Re: Ediff cannot handle C-m in output of diff Date: Tue, 4 Nov 1997 12:36:19 +0200 (IST) On Mon, 3 Nov 1997, Thorbjoern Hansen wrote: > I have trouble using Ediff under Windows NT together with a version of > 'diff' for Windows NT that insists on emitting "\C-m\C-j" instead of > only "\C-j". Ediff reports: > > Errors in diff output. Diff output is in # > > and that buffer will contain lines like > > 3c3^M > 20a21^M > 62a64,65^M > > If I change the setting of the two variables > ediff-diff-ok-lines-regexp and ediff-match-diff-line in ediff-diff.el > to include "\C-m?" before "$", Ediff will work correctly. IMHO, this is not a problem with Ediff, and therefore it's not Ediff which should correct it. These C-m (aka CR, the Carriage Return) characters should have been stripped by Emacs when it reads diff's output. This is how it works in the MS-DOS version of Emacs, although DOS versions of `diff' also write the CR characters at the end of each line. Please also note that Emacs 20 has a mechanism whereby the EOL conversion (CRLF <-> NL) on input and output happens automatically.