POSRANGE()
 Determines the position of the first character within a given ASCII code
 range
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 Syntax

     POSRANGE(<cCharacter1>,<cCharacter2>,<cString>,
        [<lMode>],[<nIgnore>]) --> nPosition

 Arguments

     <cCharacter1> and <cCharacter2>  Designate the first and the
     last character of the character range.

     <cString>  Designates the string within which to search for a
     character in the <cCharacter1> to <cCharacter2> range.

     <lMode>  Designates if the return value is within the specified
     range or outside of the range.  The default value (.F.) searches for the
     first character within the range.

     <nIgnore>  Designates the number of characters at the beginning of
     the character string that are excluded from the search.  The default
     value excludes none (zero).

 Returns

     The value returned corresponds to the position of the located character.
     If no character is found, the function returns 0.

 Description

     Beginning from the left, POSRANGE() searches for the first character in
     the range <cCharacter1> to <cCharacter2> within <cString>.  If <lMode>
     is specified as .T., then the function searches for the first character
     that is not in the specified range.  This way you could search for
     control characters within a string by specifying <cCharacter1> = CHR(0)
     and <cCharacter2> = CHR(31).

     The <nIgnore> parameter gives you the ability to exclude a particular
     number of characters at the beginning of the <cString> from the search.

 Examples

     .  Search for the first character in the character string cInput
        that is not a control character:

        cInput  :=  COM_READ(1)
        ? POSRANGE(CHR(0), CHR(31), cInput, .T.)

     .  Ignore the first 10 characters:

        ? POSRANGE(CHR(0), CHR(31), cInput, .T., 10)