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Full Discussion: While loop is running only for the first iteration
Top Forums Shell Programming and Scripting While loop is running only for the first iteration Post 303013470 by Don Cragun on Wednesday 21st of February 2018 09:45:18 PM
Old 02-21-2018
I don't have ffmpeg installed on my system. What does the final hyphen in the command:
Code:
ffmpeg -i "${FILE_NAME1}.aac" -f caf -

tell ffmpeg to do? With many utilities, that would be a request to have the utility read data from the standard input of that utility (which in this case would be the remaining lines from /tmp/mp4_List) which would cause the while read to hit EOF on the 2nd iteration through the loop.

Your script would also run faster and use fewer system resources if you would change:
Code:
cat /tmp/mp4_List |while read eachF
do
... ... ...
done

to:
Code:
while read eachF
do
... ... ...
done < /tmp/mp4_List

This User Gave Thanks to Don Cragun For This Post:
prvnrk
 

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grub-render-label

GRUB-RENDER-LABEL(1)                                               User Commands                                              GRUB-RENDER-LABEL(1)

NAME

       grub-render-label - generate a .disk_label for Apple Macs.

SYNOPSIS

       grub-render-label [OPTION...] [OPTIONS]

DESCRIPTION

       Render Apple .disk_label.

       -b, --bgcolor=COLOR
              use COLOR for background

       -c, --color=COLOR
              use COLOR for text

       -f, --font=FILE
              use FILE as font (PF2).

       -i, --input=FILE
              read text from FILE.

       -o, --output=FILE
              set output filename. Default is STDOUT

       -t, --text=STRING
              set the label to render

       -v, --verbose
              print verbose messages.

       -?, --help
              give this help list

       --usage
              give a short usage message

       -V, --version
              print program version

       Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

REPORTING BUGS

       Report bugs to <bug-grub@gnu.org>.

SEE ALSO

       The  full  documentation  for grub-render-label is maintained as a Texinfo manual.  If the info and grub-render-label programs are properly
       installed at your site, the command

              info grub-render-label

       should give you access to the complete manual.

grub-render-label (GRUB) 2.02-2ubuntu8.3                             July 2018                                                GRUB-RENDER-LABEL(1)
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