randy@umn-cs.cs.umn.edu (Randy Orrison) (06/28/88)
From the 4.3BSD (Mt. Xinu) open(2) man page: | If the O_NDELAY flag is specified and | the open call would result in the process being blocked for | some reason (e.g. waiting for carrier on a dialup line), the | open returns immediately. The first time the process | attempts to perform i/o on the open file it will block (not | currently implemented). Ok, so it's not currently implemented. What happens? If you open(2) a file with O_NDELAY and then read from it, what happens? I would guess that the read wouldn't block, but what would it do? (did i make my question clear?) Also, if a file is opened without O_NDELAY and the process blocks, can the open be interrupted? I notice in read(2) that a valid error return is EINTR, but I don't see that for open(2). Are opens uninterruptable? What's the situation on System V? (SVID/POSIX, too!) Thanks in advance! -randy (Please reply to me, if there are requests i will summarize responses here) -- Randy Orrison, Control Data, Arden Hills, MN randy@ux.acss.umn.edu {bungia, uunet!hi-csc, rutgers, sun}!umn-cs!randy "I consulted all the sages I could find in Yellow Pages, but there aren't many of them." -APP