undefined symbol: sysinfo

[trtiwari]

Hi,
I am trying to compile sysinfo with emscripten:

#include <emscripten/bind.h>
#include <sys/sysinfo.h>
int main()
{
    int days, hours, mins;
    struct sysinfo sys_info;

    if(sysinfo(&sys_info) != 0)
        perror("sysinfo");

    // Uptime
    days = sys_info.uptime / 86400;
    hours = (sys_info.uptime / 3600) - (days * 24);
    mins = (sys_info.uptime / 60) - (days * 1440) - (hours * 60);

    printf("Uptime: %ddays, %dhours, %dminutes, %ldseconds\n",
                      days, hours, mins, sys_info.uptime % 60);

    // Load Averages for 1,5 and 15 minutes
    printf("Load Avgs: 1min(%ld) 5min(%ld) 15min(%ld)\n",
          sys_info.loads[0], sys_info.loads[1], sys_info.loads[2]);

    // Total and free ram.
    printf("Total Ram: %ldk\tFree: %ldk\n", sys_info.totalram / 1024,
                                        sys_info.freeram / 1024);

    // Shared and buffered ram.
    printf("Shared Ram: %ldk\n", sys_info.sharedram / 1024);
    printf("Buffered Ram: %ldk\n", sys_info.bufferram / 1024);

    // Swap space
    printf("Total Swap: %ldk\tFree: %ldk\n", sys_info.totalswap / 1024,
                                           sys_info.freeswap / 1024);

    // Number of processes currently running.
    printf("Number of processes: %d\n", sys_info.procs);

    return 0;
}
EMSCRIPTEN_BINDINGS(my_module) {
	function("main",&main);
}

I compile it using:

emcc --bind -o wasm.js wasm.cpp

However, it always generates the following compilation error:

error: undefined symbol: sysinfo

However, I do see the sys/sysinfo.h header file at ~/emsdk/emscripten/1.38.26/system/include/libc/sys

I've noticed the same issue with many other libc header files - sys/personality.h, sys/quota.h, etc, where the header files do exist in emscripten but the compiler still generates undefined symbol errors.

Am I missing a compiler flag, or are these functions not supported?

[kripken]

We don't have full POSIX support, so stuff like sysinfo is just not yet implemented. For sysinfo specifically, we can't tell the actual system-level values of those things, like swap, so at best we could just report them as "0" probably.

[trtiwari]

I see, do you know if there is any way to get any sort of information on the device it is running on? Uname doesn't report everything too.
Thanks!

[kripken]

The question is what APIs are present. In node.js maybe they do give APIs that let you do this? On the web, which is most of our focus, it carefully sandboxes things so you can't tell stuff like swap space etc. (however, there might be APIs for specific things, like the number of cpus?)

[stale]

This issue has been automatically marked as stale because there has been no activity in the past year. It will be closed automatically if no further activity occurs in the next 7 days. Feel free to re-open at any time if this issue is still relevant.