Opening Files for Reading Only : A data file is a file that you can open and read its contents visually - for example, C source files, .dat files, HTML etc - anything that looks "neat" in Notepad. A binary file is a file that is written in machine code - usually seen as a mass of weird characters in Notepad! Examples are bitmaps, executables etc. To open a data file for reading only, pass "r" as the second argument of fopen, as demonstrated in this example:
#include
int main()
{
FILE *file; /* declare a FILE pointer */
file = fopen("data/hello.dat", "r");
/* open a text file for reading */
if(file==NULL)
{
}
else
{
}
}
printf("Error: can't open file.\n");
fclose(file); /*DON'T PASS A NULL POINTER TO fclose !! */
return 1;