tcgetsid(3) Library Functions Manual tcgetsid(3) tcgetsid - (libc -lc) #define _XOPEN_SOURCE 500 /* feature_test_macros(7) */ #include pid_t tcgetsid(int fd); tcgetsid() fd . . fd tcgetsid() . -1 errno . EBADF fd . ENOTTY fd. attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |tcgetsid() | | MT-Safe | +------------+------------------------------------+--------------------+ POSIX.1-2008. glibc 2.1. POSIX.1-2001. TIOCGSID ioctl(2) 2.1.71. getsid(2) 3 . . : . 6.18 8 2026 tcgetsid(3)