程式語言 - GNU - C/C++ - System Log

參考資訊：
https://github.com/pasce/daemon-skeleton-linux-c

main.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <syslog.h>

int main(int argc, char **argv)
{
    openlog("hello", LOG_PID, LOG_DAEMON);
    syslog(LOG_NOTICE, "Hello, world!");
    closelog();
    return 0;
}

執行

$ gcc main.c -o main
$ ./main
$ journalctl -q | grep -i hello
    May 18 10:24:13 debian hello[7323]: Hello, world!

P.S. Ubuntu系統下可以察看/var/log/syslog