buffered IO

The code I am working on is running fine on Windows.  When it is ported and  built on Linux, it fails on the  on eof our unit tests  with an error  – cannot write a file to working directory - in a directory that is open to write in.

Running the same Linux executable with strace, I get "too many open files" error trying to write the file.

Changing all buffered IO open statements from BUFFERCOUNT=4 to =1, now it runs with no errors.   Is there any known issue with buffered IO on Linux as opposed to WIndows?

thanks,

Scott