I create or open one file with fopen, then im writing to file fputs,fprintf,fputc after these functions im checking files cursor position with ftell and its ok.When i use fflush function it is not writing anything to sd card , if i use fflush+ fclose or just fclose it is writing with out problem. Flush is returns 0.
What is the problem.
STM32F103 , SD CARD,RL-FLASHFS