This post comes from my ever-growing file of ‘how the hell did I not know that’ issues.<\/p>\n
On the cluster at work we have a bunch of machines with names like mysite12 or mysite237. So quite often I’m writing shell scripts to loop through all these boxes to get info. So I do something like this:<\/p>\n
\r\nfor number in `seq 12 256`\r\ndo\r\n node=mysite$number\r\n echo $node\r\ndone\r\n<\/pre>\nWhich produces
\n
\nmysite12
\nmysite13
\n.....
\nmysite256
\n<\/code>
\nIt occurred to me today that this is such a staggeringly common thing to do that seq probably has a way of doing it already. Sure enough after reading the man page it turns out that you can hand seq a PRINTF style format command. So I can create my node names purely in seq<\/p>\n\r\nfor node in `seq -f "mysite%g" 12 255"\r\ndo\r\n echo $node\r\ndone\r\n<\/pre>\n
\nmysite12
\nmysite13
\n....
\nmysite255
\n<\/code>
\nHow has it taken me ten years to work that out? <\/p>\n","protected":false},"excerpt":{"rendered":"This post comes from my ever-growing file of ‘how the hell did I not know that’ issues. On the cluster at work we have a bunch of machines with names like mysite12 or mysite237. So quite often I’m writing shell scripts to loop through all these boxes to get info. So I do something like … Continue reading Being Slightly Smarter With seq<\/span>