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Top Forums Shell Programming and Scripting Don't understand AWK asort behaviour Post 302576136 by fpmurphy on Wednesday 23rd of November 2011 06:00:45 PM
Old 11-23-2011
In AWK, arrays are associative and array subscripts are always strings. Arrays can be sparse as in your example. If you use an array subscript (expression index) to refer to an array element that has no recorded value, i.e. T[10], then the value returned is "", the null string.

You can test whether a particular index exists, without the side effect of creating that element if it is not already present by using an
Code:
index in array

expression.

For more information, see Chapter 11 of Effective AWK Programming by Arnold Robbins.
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IGAWK(1)							 Utility Commands							  IGAWK(1)

NAME
igawk - gawk with include files SYNOPSIS
igawk [ all gawk options ] -f program-file [ -- ] file ... igawk [ all gawk options ] [ -- ] program-text file ... DESCRIPTION
Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1). AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like @include getopt.awk in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path. OPTIONS
See gawk(1) for a full description of the AWK language and the options that gawk supports. EXAMPLES
cat << EOF > test.awk @include getopt.awk BEGIN { while (getopt(ARGC, ARGV, "am:q") != -1) ... } EOF igawk -f test.awk SEE ALSO
gawk(1) Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995. AUTHOR
Arnold Robbins (arnold@skeeve.com). Free Software Foundation Nov 3 1999 IGAWK(1)
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