Variable column widths, string lengths in printf-style functions

topic: 

I have been programming in C for quite some time, but until recently I was not aware that you could specify column widths and string limits using variables. I have neither seen this functionality used in any projects until I started working with OpenSER.

Specify a variable column width:

1
printf("%*d", width, number);

Specify a variable number of characters from a string:

1
printf("%.*s", width, string);

Comments

Can you please post a link to document explaining this feature

http://linux.die.net/man/3/printf

It's described under "The field width"

http://msdn2.microsoft.com/en-us/library/25366k66.aspx

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