How can I save a file with a predefined extension?

[ahp777]

Hello everyone! I'm trying to make one complicated (for my knowledge) C program and need some help with one function. I do some stuff with a text file and I have to save the results of it in an output file which has the same name as the input file (which is not a big deal) but it has to have a ".cnt" extension. I'm not very good at programming and though I'm familiar with working with text files I can't figure out how to do this or the algorithm that does it.
Could anyone give me some advice on this?
Thank you preliminary!

[MK27]

Just add ".cnt" to the filename. That's it. If the ".cnt" is suppose to replace the current extension, then remove that first. This is just string manipulation (strcat, strrchr, sprintf etc).

[ahp777]

So, if I got you right, I have to concatenate ".cnt" to the string that contains the name of the file with strcat? Makes sense to me. Thanks for the tip! I will try it and post again if something goes wrong.

[CommonTater]

Hello everyone! I'm trying to make one complicated (for my knowledge) C program and need some help with one function. I do some stuff with a text file and I have to save the results of it in an output file which has the same name as the input file (which is not a big deal) but it has to have a ".cnt" extension. I'm not very good at programming and though I'm familiar with working with text files I can't figure out how to do this or the algorithm that does it.
Could anyone give me some advice on this?
Thank you preliminary!

Assuming the original filename has an extension already...

Use strchr() to locate the dot at the beginning of the extension.
Use strcpy() to copy the new extension over the old one.
Open the file...

[ahp777]

Thank you, Tater, it works!