Uptime under linux in C

Question

How can I retrieve uptime under linux using C? (without using popen and/or /proc)

Thanks

Answer 1

Via top or via uptime, but I don't know about any syscall, someone will for sure :)

uptime should be rather easy to parse.

Just stumbled into this:

#include 

struct sysinfo info;
sysinfo(&info);
printf("Uptime = %ld\n", info.uptime);