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--- task_boiler [2022/08/11 21:29] – raju
+++ task_boiler [2024/01/23 22:55] (current) – raju
@@ Line 3: / Line 3: @@
 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
-</code>
-we want to output
-<code>
-value
-</code>
-We can't directly use 'sort' since it will sort the header as well.
-<code>
-$ echo -e "value\n8\n2\n6\n3" | sort
-value
-</code>
-==== bare bones solution ====
-Create a script called 'body' with the following contents
-<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>
-Make it executable
-<code>
-chmod +x body
-</code>
-place it somewhere in your PATH (say ~/bin)
-<code>
-mv body ~/bin
-</code>
-This script will apply any unix command to all but the first line. For example, using it on our example
-<code>
-$ echo -e "value\n8\n2\n6\n3" | body sort
-value
-</code>
-==== practical solution ====
-I got the above script from https://github.com/jeroenjanssens/dsutils/blob/master/body . The underlying repository (https://github.com/jeroenjanssens/dsutils) contains many such useful scripts (ex:- header - to add, replace, and delete header lines). A more practical approach is to clone the entire repository and add the repo location to your PATH.