ofstream (standard C++ file output) not working

[davidalln]

Did you or anyone else successfully get a log running on their cRio? We are trying to do something similar, and we have had consistent success with creating the file but very spotty success when writing to it (depending on where the lines are added in the code). Sometimes it works sometimes it doesn't.

[slavik262]

I know this is quite a bump, but now I'm even having problems using C file I/O with FILE* pointers. I've called Priv_SetWriteAllowed(1) and still weird stuff happens. Sometimes things work fine, but there's a boat load of issues most of the time:

• While some files write fine, others don't write at all, and still others write nothing but whitespace.
• fwrite() reformats strings for some bizarre reason. Example: I wanted to print some formatted data into a .csv (comma seperated value) file. I used sprintf() to print some floats with some commas, carraige returns, and line feeds. Calling printf() on the string created with sprintf() yields what I would expect, but when I write the exact same string to the file with fwrite(), every float is smaller by two orders of magnitude.

Does anybody have any idea what could be causing this? It's making things very difficult and I can't imagine why it would be happening.

[TheDominis]

I've found that some parts of the STL do not work with well/at all Wind River. I tried to use std::fstream to store some packet data, but had to use c-style file I/O for it to work.

[slavik262]

Originally Posted by TheDominis

I've found that some parts of the STL do not work with well/at all Wind River. I tried to use std::fstream to store some packet data, but had to use c-style file I/O for it to work.

C-style file I/O isn't working for me at all either...

[TheDominis]

Originally Posted by slavik262

C-style file I/O isn't working for me at all either...

Interesting. What permissions are you using? I used "w".

[slavik262]

I was using w. I guess I could try wb or w+, but I was just writing text...