The Nicomsoft OCR SDK is also available for Linux (x86 and x64). Here are some notes about the Linux version:
The scan functions ("Scan_XXXXX") are not available.
By default, an EXE that calls "libNSOCR.so" must be placed in the "Bin" folder (that is, in the same folder). If you need to specify a different location for the OCR files, use the "Engine_SetDataDirectory" function.
All OCR functions use wide characters. In Linux, a wide character is 4 bytes.