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task_boiler [2022/08/11 21:19] rajutask_boiler [2023/08/11 20:40] raju
Line 4: Line 4:
 Start the first heading with "=====" Start the first heading with "====="
  
-===== apply unix commands to all but the first line ===== 
-==== Situation ==== 
-Let's say we want to sort a series of numbers in descending order but keep the header at the top. For example, given 
-<code> 
-$ echo -e "value\n8\n2\n6\n3" 
-value 
-8 
-2 
-6 
-3 
-</code> 
-we want to output 
-<code> 
-value 
-2 
-3 
-6 
-8 
-</code> 
  
-We can't directly use 'sort' since it will sort the header as well. 
-<code> 
-$ echo -e "value\n8\n2\n6\n3" | sort 
-2 
-3 
-6 
-8 
-value 
-</code> 
- 
-==== simple solution ==== 
-Create a script called 'body' with the following contents and place it somewhere in your PATH. 
-<code> 
-#!/usr/bin/env bash 
-# 
-# body: apply expression to all but the first line. 
-# Use multiple times in case the header spans more than one line. 
-# 
-# Example usage: 
-# $ echo -e "value\n8\n2\n6\n3" | body sort 
-# 
-IFS= read -r header 
-printf '%s\n' "$header" 
-"$@" 
-</code> 
- 
- 
-Give it  exec 
task_boiler.txt · Last modified: 2024/01/23 22:55 by raju