SVID and writev()

[Claus Tondering]

In the third edition of SVID (the edition that describes Release 4) the
following is said about the writev() system call (in write(BA_OS) in
volume 1):


  int writev(int fildes, const struct iovec *iov, int iovcnt);

  ... iovcnt is valid if greater than 0 and less than or equal
  to {IOV_MAX}.


A similar thing is said about readv().

I have not been able to find a specification of {IOV_MAX} anywhere. Unless
I have overlooked something, it is not defined or mentioned elsewhere
in the SVID. Is it supposed to be defined in an include-file, and if so,
which? And what should be its minimum value?

-- 
Claus Tondering                                       | The number of seconds
Dansk Data Elektronik A/S, Herlev, Denmark            | in a leap year is
E-mail: ct at dde.dk   or   ...!uunet!mcsun!dkuug!dde!ct | sqrt(1E15)