chroot only emulates a chroot function call
by keeping track of the current root and accomodating this in the file
related function calls. A real chroot functionality is not supported by
Windows however.
clock_getres, clock_gettime
and clock_setres only support CLOCK_REALTIME for
now.
fpclassify, isfinite,
isgreater, isgreaterequal,
isinf, isless,
islessequal, islessgreater,
isnan, isnormal,
isunordered, and signbit
only support float and double arguments, not long double arguments.
getitimer and setitimer
only support ITIMER_REAL for now.
link will copy the file if it can't implement
a true hardlink. This is true at least for FAT and FAT32 filesystems.
NTFS supports hardlinks.
lseek only works properly on binary
files.
setuid is only safe against reverting the user
switch after a call to one of the exec(2) functions took place. Windows
doesn't support a non-revertable user switch within the context of Win32
processes.
vfork just calls fork.
vhangup always returns -1 and sets errno to
ENOSYS.
The XSI IPC functions semctl,
semget, semop,
shmat, shmctl,
shmdt, shmget,
msgctl, msgget,
msgrcv and msgsnd are only
available when cygserver is running and the CYGWIN
environment variable is set so that it contains the string
server.