pidfd_getfd(2) System Calls Manual pidfd_getfd(2) pidfd_getfd - (libc -lc) #include /* SYS_* */ #include int syscall(SYS_pidfd_getfd, int pidfd, int targetfd, unsigned int flags); : glibc pidfd_getfd() syscall(2). pidfd_getfd() . targetfd PID pidfd. ( open(2)) pidfd. . ( bind(2)) . (FD_CLOEXEC fcntl(2)) pidfd_getfd(). flags . 0. ptrace PTRACE_MODE_ATTACH_REALCREDS ( ptrace(2)). pidfd_getfd() ( ). -1 errno . EBADF pidfd PID . EBADF targetfd pidfd. EINVAL flags 0. EMFILE ( RLIMIT_NOFILE getrlimit(2)). ENFILE . EPERM PTRACE_MODE_ATTACH_REALCREDS ( ptrace(2)) pidfd. ESRCH pidfd ( ). . 5.6. PID pidfd_open(2). pidfd_getfd() SCM_RIGHTS unix(7) : o SCM_RIGHTS UNIX. o SCM_RIGHTS . pidfd_getfd(). o pidfd_getfd() ptrace PTRACE_MODE_ATTACH_REALCREDS. clone3(2), dup(2), kcmp(2), pidfd_open(2) 3 . . : . 6.18 8 2026 pidfd_getfd(2)