While loop in bash executes only once

Question

I have a file sorted_result.txt, It contains the following:

00:7:11.8
00:8:32.0
00:9:16.8
00:19:1.6
00:24:22.84

When I run the following code, the while loop executes only once instead of running for each line in the file.

#!/bin/bash

input="./sorted_result.txt"

count=1
initial=00:00:00
sixty=60
while read line
do
  ffmpeg -i cnbc.avi -vcodec h264 -vf fps=25 -ss $initial -to $line $count.avi
  count=$((count + 1))
  initial=$line
done < "$input"

Please help

shellcheck.net notes that `ffmpeg` might eat the rest of your stdin, which would prevent the loop from happening again — Eric Renouf, Jun 18 '18 at 12:58
You can verifiy if @EricRenouf's hint is the problem by replacing `ffmpeg ...` with `echo ffmpeg ...`. If so, the fix is `ffmpeg ... < /dev/null`. — Jens, Jun 18 '18 at 13:00
alternately, we can read from a different file descriptor: `while read -u3 line ... 3< "$input"` — glenn jackman, Jun 18 '18 at 14:33
You can use the `ffmpeg` option `-nostdin` instead of `< /dev/null` — llogan, Jun 18 '18 at 20:11

score 1 · Accepted Answer · answered Jun 19 '18 at 06:29

1

The solution is to use -nostdin between ffmpeg and -i

answered Jun 19 '18 at 06:29

Yaser Sakkaf

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While loop in bash executes only once

1 Answers1