Getting a fully-qualified path from a PID

[Joe Marcus Clarke]

On Wed, 2004-07-21 at 11:12, Dan Nelson wrote:
> In the last episode (Jul 20), Joe Marcus Clarke said:
> > What is the canonical way for a userland application to get the
> > fully-qualified path of an executable from its running PID?  I know I
> > can do a readlink(2) on /proc/pid/file, but procfs is deprecated on
> > 5.X, correct?  Is there a more appropriate way to do this?  Thanks.
> 
> realpath(argv[0]) works for commands not run from $PATH. Commands found
> through a PATH earch will just have the basename in argv[0] so you
> would have to check each PATH element until you found it.  Note that
> /proc/pid/file won't work if vn_fullpath() fails (say the orignal file
> has been unlinked, or the filename has expired from the kernel's
> cache).
> 
> If you are examining another process, you can use the kvm_getargv() and
> kvm_getenvv() functions to fetch argv[0] and PATH out of the target
> process.

Okay, I was thinking about that.  What I was specifically interested in
was processes spawned from $PATH, so realpath isn't going to be much
good to me there.  I didn't know if there was a better way than getting
the environ+argv with kvm, then searching each path element.  Thanks for
the clarification.

Joe

-- 
PGP Key : http://www.marcuscom.com/pgp.asc
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: This is a digitally signed message part
Url : http://lists.freebsd.org/pipermail/freebsd-hackers/attachments/20040721/3ed7163c/attachment.bin