*BSD News Article 28739


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From: RHussein@uh.edu (Chunks of Code)
Newsgroups: comp.bugs.4bsd,comp.unix.bsd
Subject: BSD rcmd() bug?
Date: 26 Mar 1994 05:25:40 GMT
Organization: University of Houston
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Message-ID: <2n0h0k$3cp@masala.cc.uh.edu>
NNTP-Posting-Host: unknown@racine.cs.uh.edu
Keywords: rmcd(),select()
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I don't know if this has been fixed in BSD4.4 but I noticed the following:

In BSD4.3 rcmd() uses the rresvport() call to get a file descriptor to a
privileged port. rcmd() then uses select() to check on up to 32 file
descriptors for a read condition to occur. IF rresvport() returns an FD larger
than 32, then rcmd() will simply "hang" waiting for a read on FDs it is not
checking for. Would some kind soul post/email confirm this? Also, does anyone
know if Ultrix4.x have this problem too?

--
Reza Hussein
University of Houston