Asterik character in stream functions

Posted on 2006-11-10
Medium Priority
Last Modified: 2010-04-15
What is the use of the asterik character in stream like functions, e.g. what does the following line of code actually do?

printf(" %-*s ", 50);

I saw this in some source code, but it just prints garbage characters.  I can tell the integer parameter refers to the field length it prints, but I can't tell what the "*s" refers to.

Question by:chsalvia
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ID: 17920240
    A field width or precision, or both, may be indicated by an asterisk `*'
     or an asterisk followed by one or more decimal digits and a `$' instead
     of a digit string.  In this case, an int argument supplies the field
     width or precision.  A negative field width is treated as a left adjust-
     ment flag followed by a positive field width; a negative precision is
     treated as though it were missing.  If a single format directive mixes
     positional (nn$) and non-positional arguments, the results are undefined.
so it'd the same as
printf(" %-50s ");
which is missing a string argument

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