
sed:tldr:c733c
This command is running a shell command and piping its output to the sed
command. Let's break it down:
${command}
: This is a placeholder that represents the command whose output we want to process with sed
. It could be any valid shell command.
|
: The pipe symbol |
in Unix or Linux shell is used to redirect the output of one command as the input to another command. In this case, we are redirecting the output of ${command}
to the sed
command.
sed
: sed
stands for "stream editor" and is a powerful Unix utility for text processing and manipulation. It reads text input line by line, applies specified operations, and produces the modified output.
-n
: This option tells sed
to suppress automatic printing of input lines. Without this option, sed
would print every line of the input stream.
'1p'
: This is a sed
command that specifies an operation to be performed on the input. In this case, 1p
tells sed
to print the first line of the input.
So, when ${command}
runs and produces output, it is piped to sed
, which only prints the first line of that output.