The report generated is in the following format:
File filename1 Subroutine subname1 Package package1 object1 line numbers object2 line numbers ... Package package2 ...
Each File section reports on a single file. Each Subroutine section reports on a single subroutine apart from the special cases ``(definitions)'' and ``(main)''. These report, respectively, on subroutine definitions found by the initial symbol table walk and on the main part of the program or module external to all subroutines.
The report is then grouped by the Package of each variable, subroutine or format with the special case ``(lexicals)'' meaning lexical variables. Each object name (implicitly qualified by its containing Package) includes its type character(s) at the beginning where possible. Lexical variables are easier to track and even included dereferencing information where possible.
The "line numbers" are a comma separated list of line numbers (some preceded by code letters) where that object is used in some way. Simple uses aren't preceded by a code letter. Introductions (such as where a lexical is first defined with "my") are indicated with the letter ``i''. Subroutine and method calls are indicated by the character ``&''. Subroutine definitions are indicated by ``s'' and format definitions by ``f''.
For instance, here's part of the report from the pod2man program that comes with Perl:
Subroutine clear_noremap Package (lexical) $ready_to_print i1069, 1079 Package main $& 1086 $. 1086 $0 1086 $1 1087 $2 1085, 1085 $3 1085, 1085 $ARGV 1086 %HTML_Escapes 1085, 1085
This shows the variables used in the subroutine "clear_noremap". The variable $ready_to_print is a my() (lexical) variable, introduced (first declared with my()) on line 1069, and used on line 1079. The variable $& from the main package is used on 1086, and so on.
A line number may be prefixed by a single letter:
The most useful option the cross referencer has is to save the report to a separate file. For instance, to save the report on myperlprogram to the file report:
$ perl -MO=Xref,-oreport myperlprogram