How can I get a file's size in C? [duplicate]

Answer 1

If you have the file descriptor fstat() returns a stat structure which contain the file size.

#include 
#include 
#include 

// fd = fileno(f); //if you have a stream (e.g. from fopen), not a file descriptor.
struct stat buf;
fstat(fd, &buf);
off_t size = buf.st_size;