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jingjing yuan wrote: how to use c + + for the Jason data
You need to explain where this data comes from and exactly what you expect your C++ program to do with it.
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writing a program for send a command to INMARSAT via USB-RS232 and wait for the response coming within 20 seconds if the response not come means again send the commands to USB-RS232?
Uma Maheswari N
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You should check out the documentation (datasheets, application notes, etc...) of your microcontroller and study it (probably you are going to find available code
Also you may post on more specialized forums inr order to get better help.
Veni, vidi, vici.
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I hope you are not really asking what I think you are asking on a public forum and that this is something on the public access portal.
If not I warn you the INMARSAT protocol is proprietary and has a non disclosure agreement signed by yourself or someone who you work for. Refer the questions back thru the proper channels please and all the details are quite clear in the technical specification if you can not understand the document go back thru proper channels.
In vino veritas
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Hmmmm,
As someone who has worked with inmarsat hardware I would guess that this guy is simply asking about MODBUS response timeouts which isn't really proprietary information.
Best Wishes,
-David Delaune
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Hi everyone.
I wrote a function that should copy in a strings' array all the name of several files contained in a folder.
void get_filenames(char dir[]){
int i=0;
DIR *sd;
sd = opendir(dir);
struct dirent *dird;
printf("\nLa cartella %s contiene %d files.", dir, n_files);
seekdir(sd, 2);
for(i=0;i<n_files;i++){
dird=readdir(sd);
filenames[i]=dird->d_name;
printf("\n%s", filenames[i]);
}
closedir(sd);
}
When I call this function it seems to be alright, and the printf contained in the for cicle prints the names of files correctly... But if I try to print these names somewhere out of this function, I see that each string of filenames[] contains the last string printed in the get_filenames function, that is the last file in the folder.
I allocated filenames[] in another void function, this way:
...
filenames = malloc(n_files * sizeof(char));
for(i=0;i<n_files;i++){
filenames[i] = malloc(20 * sizeof(char));
}
...
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The line
filenames = malloc(n_files * sizeof(char));
should be
filenames = malloc(n_files * sizeof(char *));
because you use it to allocate pointers.
You don't show the declaration of filenames in the sample, but I assume it's char **.
By the way, what happens if a file in the directory has a name longer than 19 characters?
The good thing about pessimism is, that you are always either right or pleasently surprised.
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I think you'll find that the line:
filenames[i]=dird->d_name; should actually be something like:
filenames[i]=strdup(dird->d_name);
You see, dird->d_name is a location in memory that the current file's name is copied to - _but_ this location doesn't change, only the contents of the text does. What your code does is set each of the filename[] elements to hold this location. In the next iteration of the loop, the text contained there changes, but the location doesn't. So you've got all elements of filename[] holding the same address of a string.
If, on the other-hand, you make a duplicate of the string in dird->d_name and then store _that_ location into filenames[], each element of filenames[] will point to a different location in memory - locations that contain the string you're after.
Note - you should also change your last code-block.
filenames = malloc(n_files * sizeof(char*) );
So,
1) filenames should be a char** (I expect you've got it setup to be a char* currently)
2) each element (a char*) should contain the address of the duplicated string
3) No need for the filenames[i] = malloc(20 * sizeof(char) ); code.
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Thank you for the answer.
Of course I declared filenames as char**...  But I didn't know really good how the d_name variable works, then I made some mistakes... Now it's all clearer!
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You're welcome.
I'd hoped you had, though the way you used it gave me the impression it was only a char*
Glad to be of help. 
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I cannot find its implementation anywhere. MSDN is not much of a help.
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The MSDN entry[^] includes a link to a sample implementation.
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Hello
I'm create an IE addon that inject a style sheet to page.
CComBSTR scTagStyle = "STYLE";
IHTMLElement* elementStyle;
HRESULT hr = spHTMLDoc->createElement(scTagStyle, &elementStyle);
IHTMLDOMNode *domStyleNode;
hr = elementStyle->QueryInterface(IID_IHTMLDOMNode, (LPVOID*)&domStyleNode);
IHTMLStyleElement *IstyleElem;
hr = elementStyle->QueryInterface(IID_IHTMLStyleElement, (LPVOID*)&IstyleElem);
I dont know the way to set css_text to IHTMLStyleElement.
Please help me solve this problem.
Regards,
Son Dang
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Hi,
I'm trying to create .zip files within a C# application with the LZMA SDK.
The code worked immediately, but I can't figure out how to produce a .zip output, and I must have plain .zip. The 7z GUI produces .zip files with no problem, so it must be possible with the SDK.
I thought sure that changing the "algorithm" property was the answer, but running tests with that property ranging from 0 to 8 produced no apparent change in the output. Windows Explorer (7) rejects all such efforts, while the 7z GUI opens the outputs, no matter what.
I've spent too much time perusing the C++ source code for the GUI. It's obvious that the author has a command of C++ that's an order of magnitude greater than mine.
In short, what property need I set to what to yield a .zip output?
Thank you.
John
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Shouldn't you rather be looking for an answer here[^]?
> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> If it doesn't matter, it's antimatter.<
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Yes, that's where I started.
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I think you're getting confused between two different things. 7-Zip is an application that can compress and decompress several types of file, whereas the LZMA SDK is for compressing and decompressing using the LZMA algorithm.
If all you want to do is create ZIP files, then zlib would probably be a better option: http://www.zlib.net/[^] or maybe system.io.compression.zipfile[^] since you're using C#.
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LZMA SDK Copyright (C) 1999-2007 Igor Pavlov
LZMA is default and general compression method of 7z format
in 7-Zip compression program (www.7-zip.org). LZMA provides high
compression ratio and very fast decompression.
-----------------------
It doesn't mention .zip, or the other compression schemes 7 Zip handles, as coming out of LZMA, does it?
Sorry I bothered you.
John
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Like most of these zip programs you can change the compression format off the command line.
So set a command line on your compiler and follow it. The documentation to Z-Zip says
Type switches
Switch: -t7z
Format: 7Z
Example filename: archive.7z (default option)
Switch: -tgzip
Format: GZIP
Example filename: archive.gzip, archive.gz
Switch: -tzip
Format: ZIP
Example filename: archive.zip (compatible)
Switch: -tbzip2
Format: BZIP2
Example filename: archive.bzip2
Switch: -ttar
Format: TAR
Example filename: tarball.tar (UNIX and Linux)
Switch: -tiso
Format: ISO
Example filename: image.iso (may not be supported)
Switch: -tudf
Format: UDF
Example filename: disk.udf
So setup a command line to some file with -tZip and follow what it does.
In vino veritas
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Actually what iam doing now means i created one dialog on that iam drawing a image everything is working fine but its flickering continuously.so now my idea was without dialog i want to save that drawing part in memory so that it can be used for showing the report.
modified 15-May-14 5:03am.
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What? Could you please elaborate a bit your scenario?
Veni, vidi, vici.
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You have to be more specific. What does a dialog have to do with how you save an image? And what do you mean by saving the image directly in memory?
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What image and where are you trying to save it?
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