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Wrote about profile reading.
author markus schnalke <meillo@marmaro.de>
date Wed, 04 Jul 2012 16:28:39 +0200
parents 470d5db0c06c
children b7b81ae9c9d8
comparison
equal deleted inserted replaced
137:83681ad27ec8 138:cc35686f359e
102 recipient addresses from the message header, and hand the message 102 recipient addresses from the message header, and hand the message
103 over to the MSA. 103 over to the MSA.
104 For example, a wrapper script for qmail would be: 104 For example, a wrapper script for qmail would be:
105 .VS 105 .VS
106 #!/bin/sh 106 #!/bin/sh
107 # ignore command line arguments 107 exec qmail-inject # ignore command line arguments
108 exec qmail-inject
109 VE 108 VE
110 The requirement to parse the recipient addresses out of the message header 109 The requirement to parse the recipient addresses out of the message header
111 is likely to be removed in the future. 110 is likely to be removed in the future.
112 Then mmh would give the recipient addresses as command line arguments. 111 Then mmh would give the recipient addresses as command line arguments.
113 This appears to be the better interface. 112 This appears to be the better interface.
3273 3272
3274 3273
3275 3274
3276 .H2 "Profile Reading 3275 .H2 "Profile Reading
3277 .P 3276 .P
3278 FIXME XXX 3277 The MH profile contains the configuration for the user-specific MH setup.
3279 3278 MH tools read the profile right after starting up,
3280 commit 3e017a7abbdf69bf0dff7a4073275961eda1ded8 3279 as it contains the location of the user's mail storage
3281 Author: markus schnalke <meillo@marmaro.de> 3280 and similar settings that influence the whole setup.
3282 Date: Wed Jun 27 14:23:35 2012 +0200 3281 Further more, the profile contains the default switches for the tools,
3283 3282 hence, it must be read before the command line switches are processed.
3284 spost: Read profile and context now. Removed -library switch. 3283 .P
3285 spost is a full part of the mmh toolchest, hence, it shall read the 3284 For historic reasons, some MH tools did not read the profile and context.
3286 profile/context. This will remove the need to pass profile information 3285 Among them were
3287 from send to spost via command line switches. 3286 .Pn post /\c
3288 In January 2012, there had been a discussion on the nmh-workers ML 3287 .Pn spost ,
3289 whether post should read the profile/context. There wasn't a clear 3288 .Pn mhmail ,
3290 answer. It behavior was mainly motivated by the historic situation, 3289 and
3291 it seems. My opinion on the topic goes into the direction that every 3290 .Pn slocal .
3292 tool that is part of the mmh toolchest should read the profile. That 3291 The reason why these tools ignored the profile were not clearly stated.
3293 is a clear and simple concept. Using MH tools without wanting to 3292 During the discussion on the nmh-workers mailing list,
3294 interact with MH (like mhmail had been) is no more a practical problem. 3293 .[
3295 3294 nmh-workers levine post profile
3296 commit 32d4f9daaa70519be3072479232ff7be0500d009 3295 .]
3297 Author: markus schnalke <meillo@marmaro.de> 3296 David Levine posted an explanation, quoting John Romine:
3298 Date: Wed Jun 27 13:15:47 2012 +0200 3297 .QS
3299 3298 I asked John Romine and here's what he had to say, which
3300 mhmail: Read the context! 3299 agrees and provides an example that convinces me:
3301 mhmail will change from a mailx-replacment to an alternative to 3300 .QS
3302 `comp -ed prompter', thus being a send front-end. Hence, mhmail 3301 My take on this is that post should not be called by
3303 should not stay outside the profile/context respecting mmh toolchest. 3302 users directly, and it doesn't read the .mh_profile
3304 3303 (only front-end UI programs read the profile).
3305 3304 .QP
3306 slocal 3305 For example, there can be contexts where post is called
3307 3306 by a helper program (like 'mhmail') which may be run by
3307 a non-MH user. We don't want this to prompt the user
3308 to create an MH profile, etc.
3309 .QP
3310 My suggestion would be to have send pass a (hidden)
3311 `\-fileproc proc' option to post if needed. You could also
3312 use an environment variable (I think send/whatnow do
3313 this).
3314 .QE
3315 I think that's the way to go. My personal preference is to use a command line option, not an environment variable.
3316 .QE
3317 .P
3318 To solve the problem of
3319 .Pn post
3320 not honoring the
3321 .Pe fileproc
3322 profile entry,
3323 the community roughly agreed that a switch
3324 .Sw -fileproc
3325 should be added to
3326 .Pn post
3327 to be able to pass a different fileproc.
3328 I strongly disagree with this approach because it does not solve
3329 the problem; it only removes a single symptom.
3330 The problem is that
3331 .Pn post
3332 does not behave as expected.
3333 But all programs should behave as expected.
3334 Clear and simple concepts are a precondition for this.
3335 Hence, the real solution is having all MH tools read the profile.
3336 .P
3337 Yet, the problem has a further aspect.
3338 It mainly originates in
3339 .Pn mhmail .
3340 .Pn mhmail
3341 was intended to be a replacement for
3342 .Pn mailx
3343 on systems with MH installations.
3344 .Pn mhmail
3345 should have been able to use just like
3346 .Pn mailx ,
3347 but sending the message via MH's
3348 .Pn post
3349 instead of
3350 .Pn sendmail .
3351 Using
3352 .Pn mhmail
3353 should not be influenced by the question whether the user had
3354 MH set up for himself or not.
3355 .Pn mhmail
3356 did not read the profile as this requests the user to set up MH
3357 if not done yet.
3358 As
3359 .Pn mhmail
3360 used
3361 .Pn post ,
3362 .Pn post
3363 could not read the profile neither.
3364 This is the reason why
3365 .Pn post
3366 does not read the profile.
3367 This is the reason for the actual problem.
3368 It was not much of a problem because
3369 .Pn post
3370 was not intended to be used by users directly.
3371 .Pn send
3372 is the interactive front-end to
3373 .Pn post .
3374 .Pn send
3375 read the profile and passed all relevant values on the command line to
3376 .Pn post
3377 \(en an awkward solution.
3378 .P
3379 The important insight is that
3380 .Pn mhmail
3381 is no true MH tool.
3382 The concepts broke because this outlandish tool was treated as any other
3383 MH tool.
3384 Instead it should have been treated accordingly to its foreign style.
3385 The solution is not to prevent the tools reading the profile but
3386 to instruct them reading a different profile.
3387 .Pn mhmail
3388 could have set up a well-defined profile and caused all MH tools
3389 in the session use it by exporting an environment variable.
3390 With this approach, no special cases would have been introduced,
3391 no surprises would have been caused.
3392 By writing a clean-profile-wrapper, the concept could have been
3393 generalized orthogonally to the whole MH toolchest.
3394 Then Rose's motivation behind the decision that
3395 .Pn post
3396 ignores the profile, as quoted by Jeffrey Honig,
3397 .[
3398 nmh-workers post profile
3399 .]
3400 would have become possible:
3401 .QS
3402 when you run mh commands in a script, you want all the defaults to be
3403 what the man page says.
3404 when you run a command by hand, then you want your own defaults...
3405 .QE
3406 .LP
3407 Yet, I consider this explanation short-sighted.
3408 We should rather regard theses two cases as just two different MH setups,
3409 based on two different profiles.
3410 Mapping such problems on the concepts of switching between different
3411 profiles, solves them once for all.
3412 .P
3413 In mmh, the wish to have
3414 .Pn mhmail
3415 as as replacement for
3416 .Pn mailx
3417 is considered obsolete.
3418 Mmh's
3419 .Pn mhmail
3420 does no longer cover this use-case.
3421 Currently,
3422 .Pn mhmail
3423 is in a transition state.
3424 .Ci 32d4f9daaa70519be3072479232ff7be0500d009
3425 It may become a front-end to
3426 .Pn comp ,
3427 which provides an interface more convenient in some cases.
3428 In this case,
3429 .Pn mhmail
3430 will become an ordinary MH tool, reading the profile.
3431 If, however, this idea will not convince, then
3432 .Pn mhmail
3433 will be removed.
3434 .P
3435 Every program in the mmh toolchest reads the profile.
3436 The only exception is
3437 .Pn slocal ,
3438 which is not considered part of the mmh toolchest.
3439 This MDA is only distributed with mmh, currently.
3440 Mmh has no
3441 .Pn post
3442 program, but
3443 .Pn spost ,
3444 which now reads the profile.
3445 .Ci 3e017a7abbdf69bf0dff7a4073275961eda1ded8
3446 With this change,
3447 .Pn send
3448 and
3449 .Pn spost
3450 can be considered to be merged.
3451 Direct invocations of
3452 .Pn spost
3453 are only done by the to-be-changed
3454 .Pn mhmail
3455 implementation and by
3456 .Pn rcvdist ,
3457 which will require rework.
3458 .P
3459 The
3460 .Fu context_foil()
3461 function to pretend to have read an empty profile was removed.
3462 .Ci 68af8da96bea87a5541988870130b6209ce396f6
3463 All mmh tools read the profile.
3308 3464
3309 3465
3310 3466
3311 .H2 "Standard Libraries 3467 .H2 "Standard Libraries
3312 .P 3468 .P