[SOLVED] Bash one liner '[1]+ Stopped'

Sefyir · 07-19-2015, 11:49 PM

I've made up a one liner to play youtube videos but am stumped why it wants to go into Stopped

Code:

pyt() { youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl -s 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }

Some output

Code:

pyt() { youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }
+ pyt() { youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }

pyt 'Nightmare on Wax - You Wish'
+ pyt 'Nightmare on Wax - You Wish'
+ mplayer -vo null /dev/fd/3
curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12
++ grep --colour=auto -oe '"[[:alnum:]]\{11\}"'
++ sed -n 3p
echo $1 | tr ' ' +
++ cut -b 2-12
+++ echo Nightmare on Wax - You Wish
+++ tr ' ' +
++ curl 'https://www.youtube.com/results?search_query=Nightmare+on+Wax+-+You+Wish'
   Total     Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:MPlayer 1.1-4.8 (C) 2000-2012 MPlayer Team
-- --:--:-- --:--:--     0
[1]+  Stopped                 youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o - | mplayer -vo null /dev/fd/3 3<&0 < /dev/tty

fg
+ fg
youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o - | mplayer -vo null /dev/fd/3 3<&0 < /dev/tty

Playing /dev/fd/3.
100  158k    0  158k    0     0    905      0 --:--:--  0:02:59 --:--:--   905
+ youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v=6Ew85HKMcyg' -o -

It looks like curl is stopping it. However, once I type fg, it starts going again and runs successfully. Normally, it's a misplaced & causing the problem but I'm stumped here.
Any ideas?

Sefyir · 07-20-2015, 12:05 AM

I "fixed" it with a workaround by moving the $() part behind the command setting it into its own variable.

Code:

pyt() { id=$(curl 'https://www.youtube.com/results?search_query='$(echo "$1" | tr ' ' +) | grep -o '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12); youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='"$id" -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }

I guess there's some limitation in bash with too many pipes and sub-processes.

jpollard · 07-21-2015, 08:09 AM

no limits on pipes or sub-processes (other than what ulimit -a would show).

I think you have a grouping error... between the quotes and the ). Normally, I would have also expected a syntax error as the sequence "-o -" makes it outside the subprocess handling all the rest...

It is possible that is also what remained attached to the terminal and caused the block as the previous commands would not have interpreted the "-o -"... and bash never saw it due to the sequence being blocked.

Removing the $( and ) would then have allowed bash to properly interpret the command sequence... and the "-o -" would have been handled.

Sefyir · 07-21-2015, 12:09 PM

Quote:

Originally Posted by jpollard

no limits on pipes or sub-processes (other than what ulimit -a would show).

I think you have a grouping error... between the quotes and the ). Normally, I would have also expected a syntax error as the sequence "-o -" makes it outside the subprocess handling all the rest...

It is possible that is also what remained attached to the terminal and caused the block as the previous commands would not have interpreted the "-o -"... and bash never saw it due to the sequence being blocked.

Removing the $( and ) would then have allowed bash to properly interpret the command sequence... and the "-o -" would have been handled.

Thank you for looking at this.
The expected result of

Code:

youtube-dl -q --max-downloads 1 --no-playlist 'https://www.youtube.com/watch?v='$(curl 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) -o -
should translate to
youtube-dl -q --max-downloads 1 --no-playlist https://www.youtube.com/watch?v=Sy8iUI_ayuo -o -

This is supposed to pipe into mplayer. youtube-dl uses -o for output template and specifying - as stdout is supported. So it's not part of the subproccess but rather of the overall youtube-dl command.
I ended up placing the -o - behind the $() part - but this did not change anything.

Code:

pyt() { youtube-dl -q --max-downloads 1 --no-playlist -o - 'https://www.youtube.com/watch?v='$(curl -s 'https://www.youtube.com/results?search_query='$(echo $1 | tr ' ' +) | grep -oe '"[[:alnum:]]\{11\}"' | sed -n 3p | cut -b 2-12) | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }

Quote:

I think you have a grouping error... between the quotes and the )

Unfortunately I've got a lot of quotes and closing parenthesis.. I'm not sure where you're indicating.