POSIX_SPAWN_FILE_ACTIONS_ADDDUP2 (man3p)
posix_spawn_file_actions_adddup2 — add dup2 action to spawn file actions object (ADVANCED REALTIME)
posix_spawn_file_actions_adddup2 — add dup2 action to spawn file actions object (ADVANCED REALTIME)
wctype, wctype_l — define character class
strftime, strftime_l — convert date and time to a string
posix_spawnattr_setschedparam — set the spawn-schedparam attribute of a spawn attributes object (ADVANCED REALTIME)
realloc — memory reallocator
time — get time
vfwprintf, vswprintf, vwprintf — wide-character formatted output of a stdarg argument list
readlink, readlinkat — read the contents of a symbolic link
strchr — string scanning operation
pread, read — read from a file