NAME
SYNOPSIS
DESCRIPTION
OPTIONS
ENVIRONMENT
SEE ALSO
REPORTING BUGS
AUTHORS
COPYRIGHT

NAME

parrot - Parrot Virtual Machine

SYNOPSIS

parrot [-options] <file> [arguments ...]

DESCRIPTION

Parrot is a virtual machine designed to efficiently compile and execute bytecode for dynamic languages. Parrot currently hosts a variety of language implementations in various stages of completion, including Tcl, Javascript, Ruby, Lua, Scheme, PHP, Python, Perl 6, APL, and a .NET bytecode translator. Parrot is not about parrots, but we are rather fond of them, for obvious reasons.

OPTIONS

-h
--help Print the option summary on the command line.

-V
--version Print version information and exit.

-I
--include Add path to the include search path.

-L
--library Add path to the library search path.

--hash-seed [hexnum]: Sets the hash seed to the specified value. This option is useful for debugging intermittent failures, but should not be used in production. For more information about this option, see docs/dev/profiling.pod, docs/project/hacking_tips.pod, docs/running.pod, and docs/submissions.pod.
-X
--dynext Add path to the dynamic extension search path.

Run core options

These options select the runcore, which is useful for performance tuning and debugging. For more information about these options, see the "About runcores" section in docs/running.pod.

-R

--runcore [CORE]

Select the runcore. The following cores are available in Parrot, but not all may be available on your system:

  slow, bounds   bounds checking core (default)

  fast           bare-bones core without bounds-checking or 
                 context-updating

  subprof        subroutine-level profiler 
                 (see POD in 'src/runcore/subprof.c') 

  trace          bounds checking core with trace info 
                 (see 'parrot --help-debug')

  profiling      see 'docs/dev/profilling.pod'

  gcdebug        performs a full GC run before every op dispatch
                 (good for debugging GC problems)

-p

--profile Run with the slow core and print an execution profile.

-t

--trace Run with the slow core and print trace information to stderr.

See parrot --help-debug for available flag bits.

VM options

-D

--parrot-debug[=HEXFLAGS]

Turn on interpreter debug flag. See parrot --help-debug for available flag bits.

--help-debug Print the summary of debugging and tracing flag bits.

-w

--warnings Turn on warnings.

See parrot --help-debug for available flag bits.

-G

--no-gc Turn off GC.

This may prove useful for finding GC-related bugs.

Note:: Do not use this option for longer running programs: since memory is no longer recycled, it may quickly become exhausted.

-g

--gc [GC-type]

GC MS2 options

--gc-dynamic-threshold=percentage: Maximum memory wasted by GC
--gc-min-threshold=Kb

GC GMS options

--gc-nursery-size=percent of system: Size of gen0 (default 2)
--gc-debug Turn on GC (Garbage Collection) debugging.: This imposes some stress on the GC subsystem and can considerably slow down execution.
--leak-test|--destroy-at-end: Free all memory of the last interpreter. This is useful when running leak checkers.
-.
--wait Read a keystroke before starting.: This is useful when you want to attach a debugger on platforms such as Windows.
--runtime-prefix: Print the runtime prefix path and exit.

Compiler options

-d

--imcc-debug=[HEXFLAGS]

The -d switch takes an optional argument, consisting of a hexadecimal value of debug bits. If no value is supplied, 'debug' is set to 1.

To list the individual bits on the command line, use the --help-debug switch.

To produce a vary large output on stderr, run "parrot -d 0ffff ...".

-v

--verbose One -v shows which files are worked on and prints

a summary over register usage and optimization stats per subroutine. With two -v switches, parrot prints a line per individual processing step too.

-E

--pre-process-only

Preprocess source file (expand macros) and print result to stdout:
  $> parrot -E t/op/macro_10.pasm
  $> parrot -E t/op/macro_10.pasm | parrot -- -

-o

--output=FILE Act like an assembler, but do not execute the code,

unless the -r is supplied as well. If 'outputfile' ends with .pbc, 'parrot' will write a PBC file. If it ends with .pasm, 'parrot' will output a PASM file, even from PASM input. This can be useful when needing to check various optimizations, including -Op.

--output-pbc Act like an assembler, but always output bytecode,

even if the output file does not end in .pbc

-O

--optimize[=LEVEL]

Optimization levels

    -O0 no optimization (default)
    -O1 optimizations without life info (e.g. branches)
    -O  same
    -O2 optimizations with life info
    -Op rewrite I and N PASM registers most used first
    -Ot select fastest runcore
    -Oc turns on the optional/experimental tail call optimizations

See docs/dev/optimizer.pod for more information on the optimizer.

Note:: Optimization is currently an experimental feature and these options are likely to change.

-a

--pasm Assume PASM input on stdin.

-c

--pbc Assume PBC file on stdin and execute it.

NOTE: If whitespace separates the -d switch from the argument, the argument must start with a number, i.e., a decimal digit.

-r

--run-pbc Only useful after -o or --output-pbc.

Execute the program from the compiled in-memory image. If two -r options are supplied, the .pbc file is read from disc and executed. This is needed, primarily, for tests.

-y

--yydebug Turn on yydebug in yacc/bison.

<file>

If the file ends in .pbc it will be interpreted immediately.

If the file ends in .pasm, then it is parsed as PASM code. Otherwise, it is parsed as PIR code. In both cases, it will then be executed, unless the -o flag was supplied.

If the file is a single dash, input from stdin is read.

[arguments ...]

Optional arguments passed to the running program as ARGV. The program is assumed to know what to do with the arguments.

ENVIRONMENT

PARROT_RUNTIME: If this environment variable is set, parrot will use this path as its runtime prefix instead of the compiled-in path. This is useful if you want to execute a version of parrot different from the one on the "compiled-in" path.
PARROT_GC_DEBUG: Turn on the --gc-debug flag.

REPORTING BUGS

For information on how to submit a bug report, see docs/submissions.pod.

AUTHORS

Parrot is a product of the contributions of a great many people. For a list of most of these people, see CREDITS.