Setting up EWL to handle file I/O is a fairly intensive task. It requires many platform specific routines to be written. The easiest way to configure file I/O is to simply have EWL not know about it by defining EWL_OS_DISK_FILE_SUPPORT to 0. In that mode, EWL does not know about any routines requiring file manipulation such as fopen(), fread(), fwrite(), fclose(), and so on.
When EWL_OS_DISK_FILE_SUPPORT is defined to 1, many low-level file routines need to be written, and several supporting macros also need to be defined properly. First, make sure that EWL_FILENAME_MAX properly reflects the maximum length of a file name. Also, if the default internal EWL file buffer size is not appropriate, choose a new value for EWL_BUFSIZ. Once all the macros are properly defined, the following routines in file_io_target.c (where target represents the build target on which EWL will run) must be completed.