Searching from online Summary PERL built-in variables can be referenced in the program
$ - The number of rows that are printed in the current page, part of the Perl format system $! Return error number or error string according to context content $ "List Separator $ # Print Number When Digital Digital Output Format $$ Perl Interpreter Process ID $% Current Page Number $ & Current String $ (Current Project Group ID $) Current Process Truth Group ID $ * Setting 1 indicates multi-line format. Now / s now / m modifier, $, current output field separator $. The current input line number of the last read file is the current input line number $ / the current input record separator, the default is the new row $: character setting, after the string will be Separate to fill a continuous field. $; Separator used in the simulation multidimensional array. $? Returns the status of the previous external command $ @ Perl Interpreter Returned from the EVAL statement Error message $ [Array's first element Index number $ / Current Output Record Separator $] Perl Interpreter Sub-version $ ^ Current Channel The top Page Output Format Name $ ^ A Print Before Print Targeting Variables for Saving Formats $ ^ D Debug Sign $ ^ E Operating system extension error message in a non UNIX environment $ ^ f The largest file bundle value $ ^ h activated by the compiler The syntax check status $ ^ i Built-in control editor $ ^ l Send to the output Channel Paper Change Page $ ^ m Alternate Memory Pool Size $ ^ o Operating System Name $ ^ P Specifies the internal variable of the current quotation value $ ^ r Regular expression block last results worth $ ^ S Current Interpreter Status $ ^ T From the new century, the footbook is running at the beginning of the second calculated time $ ^ W Warning switch's current value $ ^ x Perl binary executable code $ _ default input / output and format matching space $ | Controls the buffer of the currently selected output file handle $ ~ Name of the current report format $ `In the last format matching information, the string $ 'in the last format match information after the string $ and the previous regular expression Search Format Matching Last Brand $
