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  1. #!/bin/bash
  2. s='asdfsdf
  3. @ 1234900 asdf dfasd
  4. asdf @ 1345900-asdfad wer
  5. @ 678900-asdfa adf '
  6. grep -oP '@\s*\K\d+?(?=900)' <<< "$s"
Success #stdin #stdout 0.01s 5556KB
comments (?)
stdin 
Standard input is empty
stdout 
1234
1345
678
https://ideone.com/jB5ABs
language:
Bash (bash 5.0.3)
created:
3 years ago
visibility:
secret

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