fwrite() and fread() in mac os x lion is taking long time in case of a shared file between linux device and MAC
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i have a simple mac "c" program which writes the data in to a raw data file located on a usb device connected to mac pc.
raw data file is stored in the device which is FAT32 file formatted.Linux "c" program which is running on the device opens the same file using fopen() and reads the same data written by mac program using fread().

fread() and fwrite() operations are too slow and taking long time to update.
mac c program:
   
    fp=fopen("/Volumes/Untitled/rawdatafile","rb+");
    
    fcntl(fileno(fp),F_NOCACHE,1);

is there any other apis or flags to open file in shared mode? 


