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Full Discussion: A little help understanding FIFOs?
Operating Systems Linux A little help understanding FIFOs? Post 88145 by deckard on Tuesday 1st of November 2005 12:46:48 PM
Old 11-01-2005
A little help understanding FIFOs?
This isn't strictly a Linux question, but... I've been working on a project to archive some streaming media for time shifting using 'mplayer' and have been using FIFOs to archive in Ogg Vorbis format:


Code:
mkfifo program_name.wav

(mplayer -ao pcm -aofile program_name.wav &)
MPLAYER_PID="`/sbin/pidof mplayer`"

(oggenc program_name.wav &)
OGGENC_PID="`/sbin/pidof oggenc`"

sleep 30m && kill -9 "$MPLAYER_PID" "$OGGENC_PID"
rm program_name.wav

That works OK. But some of the streams I archive are long (3-4 hours) and are difficult to "fast forward" through on my car player. So I'd like to break the recordings up into 5 minute segments WHILE I am encoding the stream. The problem is that when oggenc stops reading from the program_name.wav FIFO, mplayer stops streaming and won't start up again. Any ideas how I would do this without just grabbing the whole show in WAV format and then splitting it after the fact?
 

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LEARN ABOUT DEBIAN

dradio

DRADIO(1)							  DRadio Manuals							 DRADIO(1)

NAME

       dradio - Danmarks Radio netradio player

SYNOPSIS

       dradio [--nologo] [--notitle] [MPLAYER_OPTIONS]...
       dradio --help, -h
       dradio --version

DESCRIPTION

       dradio is a Danmarks Radio (DR) netradio, podcast, and TV player. It is a terminal based frontend to mplayer(1) that collects the available
       channels/podcasts for convenient browsing.

OPTIONS

       MPLAYER_OPTIONS
	      Options are passed to the mplayer child process, e.g. 'dradio -nocache' will turn off mplayer caching. See mplayer(1) for a descrip-
	      tion of the available options.

       --help, -h
	      Print help message and exit.

       --version
	      Print the version number and exit.

       --nologo
	      Do not show DR logo.

       --notitle
	      Do not try to update the title/icon text of the terminal with the currently playing menu item name.

KEYBOARD CONTROL

       k/j or up/down
	      Navigate menu 1 item up/down.

       ctrl-b/ctrl-f or pgup/pgdown
	      Navigate menu 1 page up/down.

       / and *
	      Decrease/increase volume.

       < and >
	      Previous/next podcast.

       left and right
	      Seek backward/forwards 1 minute in podcasts.

       shift-left and shift-right
	      Seek backward/forward 10 minutes in podcasts.

       t      Toggle show DR logo.

       p      Toggle pause.

       q      Quit.

       When playing streaming TV or video podcasts see mplayer(1) for keyboard controls.

FILES

       ~/.config/dradio/menu.xml
	      The menu configuration file. See dradio(5) for further details.
       ~/.config/dradio/out.log
	      mplayer stdout is redirected here.
       ~/.config/dradio/err.log
	      mplayer stderr is redirected here.
       ~/.config/dradio/input.conf
	      The mplayer input.conf configuration file. See mplayer(1) for further details.
       http://www.dr.dk/netradio/wmp.asp
	      DR netradio direct links page.
       http://www.dr.dk/Podcast
	      DR podcast direct links page.

AUTHOR

       Jess Thrysoee <jess@thrysoee.dk>

SEE ALSO

       dradio(5), dradio-config(1), mplayer(1), ncurses(3NCURSES)

DRadio								    JANUAR 2009 							 DRADIO(1)
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