fork download
copy 
  1. #!/bin/bash
  2. s='  Size: 123'
  3. grep '^[[:blank:]]+ Size: [0-9]+' <<< "$s" # Bohemian
  4. echo "---"
  5. grep -E '^[ \t]+Size: [0-9]+' <<< "$s"     # OP with -E
Success #stdin #stdout 0s 4956KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
---
  Size: 123
https://ideone.com/lCiWEy
language:
Bash (bash 5.0.3)
created:
4 years ago
visibility:
secret

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!