--- name: "parrot" section: "1" platform: "linux" package: "parrot-minimal" version: "6.6.0-1" release: "Debian 8 (Jessie)" platforms: ["linux"] url: "https://new.carta.tech/parrot" --- # parrot(1) Parrot Virtual Machine ## NAME parrot - Parrot Virtual Machine ## SYNOPSIS **parrot** \[-options\] \ \[arguments ...\] ## 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: ``` fast bare-bones core without bounds-checking or context-updating (default) slow, bounds bounds checking core trace bounds checking core with trace info (see 'parrot --help-debug') profiling see F subprof subroutine-level profiler (see POD in F) ``` - **-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. - \--numthreads \ Overrides the automatically detected number of CPU cores to set the number of OS threads. Minimum number: 2 ### Compiler options - **-O**\[level\] Valid optimizer levels: `"-O"`, `"-O1"`, `"-O2"`, `"-Op"` \-O1 enables the pre\_optimizer, runs before control flow graph (CFG) is built. It includes strength reduction and rewrites certain if/branch/label constructs. \-O2 runs afterwards, handles constant propagation, jump optimizations, removal of unused labels and dead code. \-Op applies -O2 to pasm files also. The old options -Oc and -Oj are currently ineffective. \-O defaults to -O1. - **-d**\[=HEXFLAGS\] - **--imcc-debug**\[=HEXFLAGS\] Turn on compiler debug flags. *See* `"parrot --help-debug"` for available flag bits. - **-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. - **--output-pbc** Act like an assembler, but always output bytecode, even if the output file does not end in *.pbc* - **-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*. - **-v** - **--verbose** Turn on compiler verbosity. ### \ 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. ## SEE ALSO 'docs/running.pod' Additional information on command line options. http://www.parrot.org/ The official Parrot web site. http://docs.parrot.org/ Parrot's official documentation site. http://parrot.github.com/ An alternative documentation site. ## 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*. ## COPYRIGHT Copyright (C) 2001-2014, Parrot Foundation.