<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div><span>Hi Brandon,</span></div><div><br><span></span></div><div><span>Many thanks for this. I will try to open the FIFO using the O_RDWR flag. My xmonad setup broke so badly when I upgraded my system to a more recent Ubuntu version that I am largely paralyzed work-wise because of this...</span></div><div><br><span></span></div><div><span>best</span></div><div><span>~l<br></span></div><div><br></div> <div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"> <div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"> <div dir="ltr"> <font face="Arial" size="2"> <hr size="1"> <b><span style="font-weight:bold;">From:</span></b> Brandon Allbery <allbery.b@gmail.com><br> <b><span style="font-weight: bold;">To:</span></b> Lara Michaels <laramichaels1978@yahoo.com>
<br><b><span style="font-weight: bold;">Cc:</span></b> "xmonad@haskell.org" <xmonad@haskell.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Thursday, June 28, 2012 8:00 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [xmonad] how to redirect dynamicLogXinerama output to a FIFO/named pipe?<br> </font> </div> <br>
<div id="yiv1969836751"><div dir="ltr">On Thu, Jun 21, 2012 at 9:31 AM, Lara Michaels <span dir="ltr"><<a rel="nofollow" ymailto="mailto:laramichaels1978@yahoo.com" target="_blank" href="mailto:laramichaels1978@yahoo.com">laramichaels1978@yahoo.com</a>></span> wrote:<br><div class="yiv1969836751gmail_quote"><blockquote class="yiv1969836751gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div><div style="font-size:12pt;font-family:times new roman, new york, times, serif;"><div>thank you for this, now I no longer get the error message upon starting xmonad. However, still nothing gets read by 'tail -f .xmonad-fifo'.</div>
</div></div></blockquote><div><br></div><div>Sorry for the delay on this, things have been "interesting" here of late.</div><div><br></div><div>It belatedly occurred to me that this *is* a FIFO, and as such the reader has to open it first, with O_RDWR (or what Haskell calls ReadWriteMode) or it won't get hooked up properly. (This is a POSIXism, and Linux at least is very strict about it; depending on the kernel version, you may see ENXDEV ("No such device or address") or what gets "opened" is a dummy node that will never successfully read or write data.) </div>
<div> </div><blockquote class="yiv1969836751gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div><div style="font-size:12pt;font-family:times new roman, new york, times, serif;"><div>Is there some other way to the dynamicLogXinerama information so that I can display it on an applet/appindicator?</div>
</div></div></blockquote><div><br></div><div>dynamicLogXinerama is not very flexible; the documentation notes this, and suggests an alternative which provides most of the same information while giving you flexibility (<a rel="nofollow" target="_blank" href="http://xmonad.org/xmonad-docs/xmonad-contrib/XMonad-Hooks-DynamicLog.html#v:dynamicLogXinerama">dynamicLogXinerama</a>).</div>
<div><br></div><div>All in all, POSIX FIFOs are remarkably useless (and I'm still amazed POSIX found a way to make them even less useful than they were originally) and should probably be avoided.</div><div><br></div></div>
-- <br>brandon s allbery <a rel="nofollow" ymailto="mailto:allbery.b@gmail.com" target="_blank" href="mailto:allbery.b@gmail.com">allbery.b@gmail.com</a><br>wandering unix systems administrator (available) (412) 475-9364 vm/sms<br><br>
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