Hi, I would like to know if I can obtain thread id of calling thread. Let me clarify what I mean by this. First, here is task_struct from linux kernel code. struct task_struct { struct list_head tasks; pid_t pid; pid_t tgid; struct task_struct *group_leader; /* threadgroup leader */ struct list_head thread_group; }; I understand that getpid returns tgid and gettid via __NR_gettid returns tid but according to manpage, it seems to me that it is same as what I get from getpid(). Man page of gettid: gettid() returns the thread ID of the current process. This is equal to the process ID (as returned by getpid(2)), unless the process is part of a thread group However, I would like to obtain pid of task_struct. Is there any way I can get that information? Thank you. YEH