TRUNCF (man3p)
truncf, truncl — round to truncated integer value
truncf, truncl — round to truncated integer value
tcgetsid — get the process group ID for the session leader for the controlling terminal
sched_setparam — set scheduling parameters (REALTIME)
isunordered — test if arguments are unordered
fchdir — change working directory
inet_addr, inet_ntoa — IPv4 address manipulation
sigpause — remove a signal from the signal mask and suspend the thread
cexp, cexpf, cexpl — complex exponential functions
islessequal — test if x is less than or equal to y
mq_receive, mq_timedreceive — receive a message from a message queue (REALTIME)