Re: cua* on kernel 2.1 and beyond

Vern Hoxie (
Fri, 4 Dec 1998 08:13:25 -0700

On Thu, 3 Dec 1998, Tymm Twillman wrote:

> ln -s /dev/ttyS0 /dev/cua0

This is bad!

A process using /dev/cua0 will create a lockfile named cua0. Another
process wanting to use /dev/ttyS0, will look for a lockfile named
ttyS0. When it is not found, that process will go ahead and open
ttyS0 and collide with the data being transferred on cua0.

A complex locking routine can be used. See my blurb on lockfiles and
a sample routine to creat either dual lockfiles or single ones.

This is available from via ftp. The tarball is


Vernon C. Hoxie                           
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