I am writing to a file using python. The script suddenly stops running and throws an \'IOError: [Errno 27] File too large\' Is there a limit on the size of the file that you
This Python bug report indicates that the OS is the source of this error message, not Python.
Since you are writing to a FAT partition, and the maximum file size limit is 4GB for FAT 32 (LinuxFilesystemsExplained) this is most likely the cause of your problem. Running your program on a system or partition with a different file system would tell you for sure.
I also got this error when I had too many files in one directory. I had 64435
files in a directory, each with 10 digits + '.json' in their names, and any subsequent attempts to write new files to the directory threw errors (e.g.) OSError: [Errno 27] File too large: 'ngrams/0/0/0/0000029503.json'
When files get too large, addressing becomes an issue. Typically you get 32 bits which translates to a maximum size of about 4 gb.