Pre-defined variables commonly used in Perl

Perl provides a number of pre-defined variables, and some of the predefined variables that are commonly used are listed below:

$_                   The default space variable to use when performing input and mode search operations $.               The current line number in the      file that was last processed [email protected]                    Perl syntax error message provided by the most recent eval () operator $!                    get current error message value, commonly used in die command $$                    The PERL process number that is executing the script $perl_version / $^v perl version, child version, and revision information for the interpreter @argv                 contains command-line arguments argv                  a special file handle that iterates through all the file names that appear in the @argv @inc        &nbspSearch path for;         library file @_                    in subroutines, the @_ variable contains the variable content passed to the subroutine%env                  associative array type variable%ENV contains current environment information%sig                  associative array type variable% The sig contains a handle to the signal content $|                   if nonzero, immediately flush on output$<,$>                real user id,  Effective user id$1,$2, ...          ordered  parentheses regex capture$/                   inpuT record separator 

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Pre-defined variables commonly used in Perl