Need clarification about a sed syntax

[RobertX]

My question is concerned with the following command:

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date | cut -c5-11,25- | sed 's/\([0-9]\{1,2\}\)/\1,/'

The output is the following:

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May 8, 2012

I tried altering the sed syntax to something like the following, where the max string, which used to be 1, 2 is changed to 1, 4 like so:

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date | cut -c5-11,25- | sed 's/\([0-9]\{1,4\}\)/\1,/'

and it still outputs the following:

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May 8, 2012

I thought maybe if the computer would see that there are four number strings as max instead of two, it would take 2012 into consideration, and would probably output this:

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May 8, 2012,

What is the error of my thinking?

[xenopeek]

You know that you can specify the output format of date

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date +'%B %-d, %Y,'

Nicely prints:

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May 9, 2012,

Run "man date" from the terminal for other format options.

Or to do it with sed, include the g modifier at the end to indicate you want to do the substitution globally (repeatedly, instead of just the first occurrence).

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date | cut -c5-11,25- | sed 's/\([0-9]\{1,4\}\)/\1,/g'

I like the solution without sed better though

[RobertX]

You know that you can specify the output format of date
Or to do it with sed, include the g modifier at the end to indicate you want to do the substitution globally (repeatedly, instead of just the first occurrence).

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date | cut -c5-11,25- | sed 's/\([0-9]\{1,4\}\)/\1,/g'

That's right! How did I forget about that?!?

[xenopeek]

Ah well, it is often the smallest things that you overlook as you stare at something not working