Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.albasani.net!feeder.news-service.com!ecngs!feeder.ecngs.de!Xl.tags.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!local2.nntp.ams.giganews.com!nntp.brightview.co.uk!news.brightview.co.uk.POSTED!not-for-mail NNTP-Posting-Date: Wed, 27 Apr 2011 08:01:01 -0500 From: "Ste (news)" Subject: Re: Online RISC OS colour converter Newsgroups: comp.sys.acorn.programmer Date: Wed, 27 Apr 2011 14:00:41 +0100 Message-ID: <51ca81058dsteve@revi11.plus.com> References: <2ff1dcca-09ac-4de2-b3c0-dce9b328eb83@17g2000prr.googlegroups.com> <92050f20-60c9-403f-b7c5-57fab28617c9@z31g2000vbs.googlegroups.com> <6b45a6aa-08ca-4cbc-b2c9-15746c3012aa@u26g2000vby.googlegroups.com> User-Agent: Pluto/3.04d (RISC-OS/5.11) NewsHound/v1.50-32 Organization: None Lines: 37 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-pi6gF4XwkY+eti3guqAswWCCmprrgByy/iiyQtYmx2qrKBzAriUEdbO0ETsYWriQ9ygwnf+dLxVkSkF!e2zdV3xZ1YmDIhzhztdy86C9jknwP2nwOJrTzrzMjPQJyjnmUhdmBUBTS+901sZgDxOjMv+kdo1u!+Q== X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2873 Xref: x330-a1.tempe.blueboxinc.net comp.sys.acorn.programmer:220 In article <6b45a6aa-08ca-4cbc-b2c9-15746c3012aa@u26g2000vby.googlegroups.com>, Gerph wrote: > Amusingly (to me) 'Use TaskWindow' isn't actually on the list, despite it > being a general encompassment of 3 or 4 of the things on the list. ISTR > the former has pathological cases which can occur more the more you use > it, which corrupt the memory that is used for its buffers (RMA in the > failing versions, IIRC). The latter has race conditions aplenty, which > affect multiple other OS components. Worst case is that you stiff the > machine completely when you trigger it. Next worst is that you trigger a > repeating exception error box. It is increasingly likely the higher the > load on the OS, which is (generally) the times at which you wish to use it. Yes. I did a classic cock-up one time in writing a command line program which processed a sprite file in some way. The processing involved redirecting output to a sprite, doing something and restoring output. This is fine if you run it in a command window or some other single-tasking context. As soon as you run it in a Task Window, there's the risk that it pre-empts away from you in the middle of the process and things get rather confused because output is still redirected into the sprite... In the end, I had to bodge a work-around which checks to see if the program is running in a Task Windows (SWI TaskWindow_TaskInfo) and if it is, push something onto the SVC stack before the sprite manipulation and pop it afterwards (the Task Window won't pre-empt when the SVC stack is non-empty). As you say: Tra-la-la-la. Ta, Steve -- Steve Revill @ Home Note: All opinions expressed herein are my own.