U

Function Classification Cancel ISR Signal Thread
ualarm() Standard Unix; removed from POSIX.1-2008 No No Yes Yes
ultoa() QNX 4 No Yes Yes Yes
ulltoa() Unix No Yes Yes Yes
umask() POSIX 1003.1 No No Yes Yes
umount() QNX Neutrino Yes No No Yes
UNALIGNED_PUT16() QNX Neutrino No Yes Yes Yes
UNALIGNED_PUT32() QNX Neutrino No Yes Yes Yes
UNALIGNED_PUT64() QNX Neutrino No Yes Yes Yes
UNALIGNED_RET16() QNX Neutrino No Yes Yes Yes
UNALIGNED_RET32() QNX Neutrino No Yes Yes Yes
UNALIGNED_RET64() QNX Neutrino No Yes Yes Yes
uname() POSIX 1003.1 No No Yes Yes
ungetc() ANSI POSIX 1003.1 Yes No No Yes
ungetwc() ANSI POSIX 1003.1 Yes No No Yes
unlink() POSIX 1003.1 Yes No Yes Yes
unlockpt() POSIX 1003.1 No No Yes Yes
unsetenv() POSIX 1003.1 No No Yes Yes
usleep() Standard Unix; removed from POSIX.1-2008 Yes No Yes Yes
utime() POSIX 1003.1 No No Yes Yes
utimes() POSIX 1003.1 XSI No No Yes Yes
utmpname() Unix Yes No Yes Yes
utoa() QNX 4 No Yes Yes Yes