Shell keyword 「while」

type while

執行

$ type while

顯示

while is a shell keyword

help while

執行

$ help while

顯示

while: while COMMANDS; do COMMANDS; done
    Execute commands as long as a test succeeds.

    Expand and execute COMMANDS as long as the final command in the
    `while' COMMANDS has an exit status of zero.

    Exit Status:
    Returns the status of the last command executed.

範例001

server.sh

#!/usr/bin/env bash

while true; do

        date;

        sleep 1;

done

設定可執行

$ chmod u+x server.sh

執行

$ ./server.sh