Use of underscores in chm filenames

[Guest]

Hi Everyone,

I recently came across the following as a result of a web search..

Location

http://alist.adobe.co.uk/devnet/robohelp/articles/merged_help_06.html

Potential problem highlighted with merged projects

"CHM filenames
Avoid the use of underscores, the hash symbol and suchlike in the names of the CHM files you create. They have been found to cause problems with merged Microsoft HTML help. Stick with alphanumeric characters and no spaces."

Has anyone experienced problems related to this and if so what exactly?

I am usually led to believe that underscores in a filename is a fairly safe practice???

[Peter Grainge]

And usually it is safe. However, there was a post on these forums where someone was having a problem and the response was that underscores in filenames for merged HTML help is a known problem. I don't work with merged CHMs but the person concerned does so...

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See www.grainge.org for RoboHelp and Authoring tips

[Guest]

Thanks Peter,

Mostly I work with web help but I have to maintain one legacy help systems as HTML help hence my interest.

[RoboColum_n_]

I'm not sure if I am the person Peter was referring to but let me add my 2p worth 😉

I have used merged CHMs for over 10 years and in the past I have had problems with underscores in the file name. The problem I faced was that file names with underscores just did not appear in the merged project output at all. Remove the underscore and it did. That was back in the days of RHX4 so things may have changed but I've never tempted fate!

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Read the RoboColum(n) for a tips,  tricks and musings on the Technical Communication Suite products.

[Guest]

Hi Colum,

Colum McAndrew wrote:

I'm not sure if I am the person Peter was referring to but let me add my 2p worth 😉

I have used merged CHMs for over 10 years and in the past I have had problems with underscores in the file name. The problem I faced was that file names with underscores just did not appear in the merged project output at all. Remove the underscore and it did. That was back in the days of RHX4 so things may have changed but I've never tempted fate!

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Read the RoboColum(n) for a tips,  tricks and musings on the Technical Communication Suite products.

Thanks for that. To be honest I was wondering of this issue might be related to a problem I've been observing with html help projects where the compiled output files revert unprompted to the same version as the baggage files. I've been unable to see what's causing that problem and whilst searching the web I came up the Adobe pages I quoted. As this was a potentially different issue I started a separate discussion...

[Guest]

This was my previous post about the merged help problem by the way....

Merged HTML help project slave chms reverting to earlier versions umprompted

[Amebr]

I replied previously to your other post and just want to say here that none of our help files have underscores or other characters - letters only. So I don't

think the problem is linked to underscores in filenames.

I'll post this in the other discussion also, to keep it all together.

[CraigCC]

Hi Authorcare,

I can confirm that unusual characters used for .chm filenames can caused problems with merging. It is not just underscores if I remember rightly and will try and dig out a list of characters to avoid.

Not tested this in V8 but like Colum I just have the habit of avoiding unusual characters now.

Looking at your other thread, it looks like this many not be the issue. Do you use RH Source Control?

Kind Regards

Craig

[Guest]

Thanks for your reply. Re source control, I don't use it. I've not really had problems with underscores in RH6 or 8 so I thought but will keep an eye on it and report any discoveries throught the other thread. I'll now consider this one closed.

Cheers

Author Care.

[Pete_Lees]

Hi, Author Care,

Space characters in the names of Help files are known to cause problems, at least as far as merged Help collections are concerned. Hash symbols (#) are a definite no-no, too, for the reasons outlined in this Microsoft Knowledge Base article:

http://support.microsoft.com/?kbid=319247

This is true also of other characters that have special significance in Web authoring, such as the question mark. I don't believe that I've ever had problems with underscores, however. Perhaps this is a RoboHelp-specific issue.

Pete

[Peter Grainge · Accepted solution]

If Pete says underscores should not cause a problem, they should not.

That said, with both Colum and Craig having experienced this, it looks like it could be a RoboHelp specific issue. It could also be a historic thing, who knows?

If you have a burning desire to use underscores, I would say go ahead but remember this thread if you do hit problems. If there is no need to use them, then to RoboHelp users I suggest it might be something best avoided.

Remember the issue is only with merged CHMs too.

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See www.grainge.org for RoboHelp and Authoring tips

[RoboColum_n_]

I have definitely hit problems in the past but I am long enough in the tooth to accept this was sometime ago. I've just stuck with what I know works. I wouldn't dream of suggesting Craig is also long in the tooth 🙂 but suspect he does likewise. If you decide to try using underscores, best of luck but as Peter says, remember our albeit historic problems.

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Read the RoboColum(n) for a tips,  tricks and musings on the Technical Communication Suite products.

[Guest]

I had the problem, but it appears to have gone away after I listed all files in the project in the [MERGE FILES] section of all of the help project file (.hhp).  This section should list all chm files except for the one that is generated by a particular project file.

If this is not sufficient, there is another change that I made at the same time. In the Window definition. I specified the Master.chm file in the window definition in every project file.

TriPane="Master_Window_Title","Master.chm::\contents.hhc","index.hhk","topicfilename.htm","ms-its:Master.chm::hometopic.htm",,,,,0x63520,,0x84e,[139,71,1026,917],0x30000,,,,,,0

I also retained a secondary window definition for the unmerged help, although you shouldn't need it if you're just opening in context of the master table of contents and index. Here it is for comparison.

Tripane2="Slave_Help_Title","contents.hhc","index.hhk","defaultfile.htm","ms-its:Slave.chm::hometopic.htm",,,,,0x63520,,0x84e,[139,71,1026,917],0x30000,,,,,,0 !