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| 129 | .\" ======================================================================== |
| 130 | .\" |
| 131 | .IX Title "Opcode 3" |
| 132 | .TH Opcode 3 "2001-09-21" "perl v5.8.8" "Perl Programmers Reference Guide" |
| 133 | .SH "NAME" |
| 134 | Opcode \- Disable named opcodes when compiling perl code |
| 135 | .SH "SYNOPSIS" |
| 136 | .IX Header "SYNOPSIS" |
| 137 | .Vb 1 |
| 138 | \& use Opcode; |
| 139 | .Ve |
| 140 | .SH "DESCRIPTION" |
| 141 | .IX Header "DESCRIPTION" |
| 142 | Perl code is always compiled into an internal format before execution. |
| 143 | .PP |
| 144 | Evaluating perl code (e.g. via \*(L"eval\*(R" or \*(L"do 'file'\*(R") causes |
| 145 | the code to be compiled into an internal format and then, |
| 146 | provided there was no error in the compilation, executed. |
| 147 | The internal format is based on many distinct \fIopcodes\fR. |
| 148 | .PP |
| 149 | By default no opmask is in effect and any code can be compiled. |
| 150 | .PP |
| 151 | The Opcode module allow you to define an \fIoperator mask\fR to be in |
| 152 | effect when perl \fInext\fR compiles any code. Attempting to compile code |
| 153 | which contains a masked opcode will cause the compilation to fail |
| 154 | with an error. The code will not be executed. |
| 155 | .SH "NOTE" |
| 156 | .IX Header "NOTE" |
| 157 | The Opcode module is not usually used directly. See the ops pragma and |
| 158 | Safe modules for more typical uses. |
| 159 | .SH "WARNING" |
| 160 | .IX Header "WARNING" |
| 161 | The authors make \fBno warranty\fR, implied or otherwise, about the |
| 162 | suitability of this software for safety or security purposes. |
| 163 | .PP |
| 164 | The authors shall not in any case be liable for special, incidental, |
| 165 | consequential, indirect or other similar damages arising from the use |
| 166 | of this software. |
| 167 | .PP |
| 168 | Your mileage will vary. If in any doubt \fBdo not use it\fR. |
| 169 | .SH "Operator Names and Operator Lists" |
| 170 | .IX Header "Operator Names and Operator Lists" |
| 171 | The canonical list of operator names is the contents of the array |
| 172 | PL_op_name defined and initialised in file \fIopcode.h\fR of the Perl |
| 173 | source distribution (and installed into the perl library). |
| 174 | .PP |
| 175 | Each operator has both a terse name (its opname) and a more verbose or |
| 176 | recognisable descriptive name. The opdesc function can be used to |
| 177 | return a list of descriptions for a list of operators. |
| 178 | .PP |
| 179 | Many of the functions and methods listed below take a list of |
| 180 | operators as parameters. Most operator lists can be made up of several |
| 181 | types of element. Each element can be one of |
| 182 | .IP "an operator name (opname)" 8 |
| 183 | .IX Item "an operator name (opname)" |
| 184 | Operator names are typically small lowercase words like enterloop, |
| 185 | leaveloop, last, next, redo etc. Sometimes they are rather cryptic |
| 186 | like gv2cv, i_ncmp and ftsvtx. |
| 187 | .IP "an operator tag name (optag)" 8 |
| 188 | .IX Item "an operator tag name (optag)" |
| 189 | Operator tags can be used to refer to groups (or sets) of operators. |
| 190 | Tag names always begin with a colon. The Opcode module defines several |
| 191 | optags and the user can define others using the define_optag function. |
| 192 | .IP "a negated opname or optag" 8 |
| 193 | .IX Item "a negated opname or optag" |
| 194 | An opname or optag can be prefixed with an exclamation mark, e.g., !mkdir. |
| 195 | Negating an opname or optag means remove the corresponding ops from the |
| 196 | accumulated set of ops at that point. |
| 197 | .IP "an operator set (opset)" 8 |
| 198 | .IX Item "an operator set (opset)" |
| 199 | An \fIopset\fR as a binary string of approximately 44 bytes which holds a |
| 200 | set or zero or more operators. |
| 201 | .Sp |
| 202 | The opset and opset_to_ops functions can be used to convert from |
| 203 | a list of operators to an opset and \fIvice versa\fR. |
| 204 | .Sp |
| 205 | Wherever a list of operators can be given you can use one or more opsets. |
| 206 | See also Manipulating Opsets below. |
| 207 | .SH "Opcode Functions" |
| 208 | .IX Header "Opcode Functions" |
| 209 | The Opcode package contains functions for manipulating operator names |
| 210 | tags and sets. All are available for export by the package. |
| 211 | .IP "opcodes" 8 |
| 212 | .IX Item "opcodes" |
| 213 | In a scalar context opcodes returns the number of opcodes in this |
| 214 | version of perl (around 350 for perl\-5.7.0). |
| 215 | .Sp |
| 216 | In a list context it returns a list of all the operator names. |
| 217 | (Not yet implemented, use \f(CW@names\fR = opset_to_ops(full_opset).) |
| 218 | .IP "opset (\s-1OP\s0, ...)" 8 |
| 219 | .IX Item "opset (OP, ...)" |
| 220 | Returns an opset containing the listed operators. |
| 221 | .IP "opset_to_ops (\s-1OPSET\s0)" 8 |
| 222 | .IX Item "opset_to_ops (OPSET)" |
| 223 | Returns a list of operator names corresponding to those operators in |
| 224 | the set. |
| 225 | .IP "opset_to_hex (\s-1OPSET\s0)" 8 |
| 226 | .IX Item "opset_to_hex (OPSET)" |
| 227 | Returns a string representation of an opset. Can be handy for debugging. |
| 228 | .IP "full_opset" 8 |
| 229 | .IX Item "full_opset" |
| 230 | Returns an opset which includes all operators. |
| 231 | .IP "empty_opset" 8 |
| 232 | .IX Item "empty_opset" |
| 233 | Returns an opset which contains no operators. |
| 234 | .IP "invert_opset (\s-1OPSET\s0)" 8 |
| 235 | .IX Item "invert_opset (OPSET)" |
| 236 | Returns an opset which is the inverse set of the one supplied. |
| 237 | .IP "verify_opset (\s-1OPSET\s0, ...)" 8 |
| 238 | .IX Item "verify_opset (OPSET, ...)" |
| 239 | Returns true if the supplied opset looks like a valid opset (is the |
| 240 | right length etc) otherwise it returns false. If an optional second |
| 241 | parameter is true then verify_opset will croak on an invalid opset |
| 242 | instead of returning false. |
| 243 | .Sp |
| 244 | Most of the other Opcode functions call verify_opset automatically |
| 245 | and will croak if given an invalid opset. |
| 246 | .IP "define_optag (\s-1OPTAG\s0, \s-1OPSET\s0)" 8 |
| 247 | .IX Item "define_optag (OPTAG, OPSET)" |
| 248 | Define \s-1OPTAG\s0 as a symbolic name for \s-1OPSET\s0. Optag names always start |
| 249 | with a colon \f(CW\*(C`:\*(C'\fR. |
| 250 | .Sp |
| 251 | The optag name used must not be defined already (define_optag will |
| 252 | croak if it is already defined). Optag names are global to the perl |
| 253 | process and optag definitions cannot be altered or deleted once |
| 254 | defined. |
| 255 | .Sp |
| 256 | It is strongly recommended that applications using Opcode should use a |
| 257 | leading capital letter on their tag names since lowercase names are |
| 258 | reserved for use by the Opcode module. If using Opcode within a module |
| 259 | you should prefix your tags names with the name of your module to |
| 260 | ensure uniqueness and thus avoid clashes with other modules. |
| 261 | .IP "opmask_add (\s-1OPSET\s0)" 8 |
| 262 | .IX Item "opmask_add (OPSET)" |
| 263 | Adds the supplied opset to the current opmask. Note that there is |
| 264 | currently \fIno\fR mechanism for unmasking ops once they have been masked. |
| 265 | This is intentional. |
| 266 | .IP "opmask" 8 |
| 267 | .IX Item "opmask" |
| 268 | Returns an opset corresponding to the current opmask. |
| 269 | .IP "opdesc (\s-1OP\s0, ...)" 8 |
| 270 | .IX Item "opdesc (OP, ...)" |
| 271 | This takes a list of operator names and returns the corresponding list |
| 272 | of operator descriptions. |
| 273 | .IP "opdump (\s-1PAT\s0)" 8 |
| 274 | .IX Item "opdump (PAT)" |
| 275 | Dumps to \s-1STDOUT\s0 a two column list of op names and op descriptions. |
| 276 | If an optional pattern is given then only lines which match the |
| 277 | (case insensitive) pattern will be output. |
| 278 | .Sp |
| 279 | It's designed to be used as a handy command line utility: |
| 280 | .Sp |
| 281 | .Vb 2 |
| 282 | \& perl -MOpcode=opdump -e opdump |
| 283 | \& perl -MOpcode=opdump -e 'opdump Eval' |
| 284 | .Ve |
| 285 | .SH "Manipulating Opsets" |
| 286 | .IX Header "Manipulating Opsets" |
| 287 | Opsets may be manipulated using the perl bit vector operators & (and), | (or), |
| 288 | ^ (xor) and ~ (negate/invert). |
| 289 | .PP |
| 290 | However you should never rely on the numerical position of any opcode |
| 291 | within the opset. In other words both sides of a bit vector operator |
| 292 | should be opsets returned from Opcode functions. |
| 293 | .PP |
| 294 | Also, since the number of opcodes in your current version of perl might |
| 295 | not be an exact multiple of eight, there may be unused bits in the last |
| 296 | byte of an upset. This should not cause any problems (Opcode functions |
| 297 | ignore those extra bits) but it does mean that using the ~ operator |
| 298 | will typically not produce the same 'physical' opset 'string' as the |
| 299 | invert_opset function. |
| 300 | .SH "TO DO (maybe)" |
| 301 | .IX Header "TO DO (maybe)" |
| 302 | .Vb 1 |
| 303 | \& $bool = opset_eq($opset1, $opset2) true if opsets are logically eqiv |
| 304 | .Ve |
| 305 | .PP |
| 306 | .Vb 1 |
| 307 | \& $yes = opset_can($opset, @ops) true if $opset has all @ops set |
| 308 | .Ve |
| 309 | .PP |
| 310 | .Vb 1 |
| 311 | \& @diff = opset_diff($opset1, $opset2) => ('foo', '!bar', ...) |
| 312 | .Ve |
| 313 | .SH "Predefined Opcode Tags" |
| 314 | .IX Header "Predefined Opcode Tags" |
| 315 | .IP ":base_core" 5 |
| 316 | .IX Item ":base_core" |
| 317 | .Vb 1 |
| 318 | \& null stub scalar pushmark wantarray const defined undef |
| 319 | .Ve |
| 320 | .Sp |
| 321 | .Vb 1 |
| 322 | \& rv2sv sassign |
| 323 | .Ve |
| 324 | .Sp |
| 325 | .Vb 1 |
| 326 | \& rv2av aassign aelem aelemfast aslice av2arylen |
| 327 | .Ve |
| 328 | .Sp |
| 329 | .Vb 1 |
| 330 | \& rv2hv helem hslice each values keys exists delete |
| 331 | .Ve |
| 332 | .Sp |
| 333 | .Vb 3 |
| 334 | \& preinc i_preinc predec i_predec postinc i_postinc postdec i_postdec |
| 335 | \& int hex oct abs pow multiply i_multiply divide i_divide |
| 336 | \& modulo i_modulo add i_add subtract i_subtract |
| 337 | .Ve |
| 338 | .Sp |
| 339 | .Vb 2 |
| 340 | \& left_shift right_shift bit_and bit_xor bit_or negate i_negate |
| 341 | \& not complement |
| 342 | .Ve |
| 343 | .Sp |
| 344 | .Vb 2 |
| 345 | \& lt i_lt gt i_gt le i_le ge i_ge eq i_eq ne i_ne ncmp i_ncmp |
| 346 | \& slt sgt sle sge seq sne scmp |
| 347 | .Ve |
| 348 | .Sp |
| 349 | .Vb 1 |
| 350 | \& substr vec stringify study pos length index rindex ord chr |
| 351 | .Ve |
| 352 | .Sp |
| 353 | .Vb 1 |
| 354 | \& ucfirst lcfirst uc lc quotemeta trans chop schop chomp schomp |
| 355 | .Ve |
| 356 | .Sp |
| 357 | .Vb 1 |
| 358 | \& match split qr |
| 359 | .Ve |
| 360 | .Sp |
| 361 | .Vb 1 |
| 362 | \& list lslice splice push pop shift unshift reverse |
| 363 | .Ve |
| 364 | .Sp |
| 365 | .Vb 1 |
| 366 | \& cond_expr flip flop andassign orassign and or xor |
| 367 | .Ve |
| 368 | .Sp |
| 369 | .Vb 1 |
| 370 | \& warn die lineseq nextstate scope enter leave setstate |
| 371 | .Ve |
| 372 | .Sp |
| 373 | .Vb 1 |
| 374 | \& rv2cv anoncode prototype |
| 375 | .Ve |
| 376 | .Sp |
| 377 | .Vb 1 |
| 378 | \& entersub leavesub leavesublv return method method_named -- XXX loops via recursion? |
| 379 | .Ve |
| 380 | .Sp |
| 381 | .Vb 1 |
| 382 | \& leaveeval -- needed for Safe to operate, is safe without entereval |
| 383 | .Ve |
| 384 | .IP ":base_mem" 5 |
| 385 | .IX Item ":base_mem" |
| 386 | These memory related ops are not included in :base_core because they |
| 387 | can easily be used to implement a resource attack (e.g., consume all |
| 388 | available memory). |
| 389 | .Sp |
| 390 | .Vb 1 |
| 391 | \& concat repeat join range |
| 392 | .Ve |
| 393 | .Sp |
| 394 | .Vb 1 |
| 395 | \& anonlist anonhash |
| 396 | .Ve |
| 397 | .Sp |
| 398 | Note that despite the existence of this optag a memory resource attack |
| 399 | may still be possible using only :base_core ops. |
| 400 | .Sp |
| 401 | Disabling these ops is a \fIvery\fR heavy handed way to attempt to prevent |
| 402 | a memory resource attack. It's probable that a specific memory limit |
| 403 | mechanism will be added to perl in the near future. |
| 404 | .IP ":base_loop" 5 |
| 405 | .IX Item ":base_loop" |
| 406 | These loop ops are not included in :base_core because they can easily be |
| 407 | used to implement a resource attack (e.g., consume all available \s-1CPU\s0 time). |
| 408 | .Sp |
| 409 | .Vb 6 |
| 410 | \& grepstart grepwhile |
| 411 | \& mapstart mapwhile |
| 412 | \& enteriter iter |
| 413 | \& enterloop leaveloop unstack |
| 414 | \& last next redo |
| 415 | \& goto |
| 416 | .Ve |
| 417 | .IP ":base_io" 5 |
| 418 | .IX Item ":base_io" |
| 419 | These ops enable \fIfilehandle\fR (rather than filename) based input and |
| 420 | output. These are safe on the assumption that only pre-existing |
| 421 | filehandles are available for use. To create new filehandles other ops |
| 422 | such as open would need to be enabled. |
| 423 | .Sp |
| 424 | .Vb 1 |
| 425 | \& readline rcatline getc read |
| 426 | .Ve |
| 427 | .Sp |
| 428 | .Vb 1 |
| 429 | \& formline enterwrite leavewrite |
| 430 | .Ve |
| 431 | .Sp |
| 432 | .Vb 1 |
| 433 | \& print sysread syswrite send recv |
| 434 | .Ve |
| 435 | .Sp |
| 436 | .Vb 1 |
| 437 | \& eof tell seek sysseek |
| 438 | .Ve |
| 439 | .Sp |
| 440 | .Vb 1 |
| 441 | \& readdir telldir seekdir rewinddir |
| 442 | .Ve |
| 443 | .IP ":base_orig" 5 |
| 444 | .IX Item ":base_orig" |
| 445 | These are a hotchpotch of opcodes still waiting to be considered |
| 446 | .Sp |
| 447 | .Vb 1 |
| 448 | \& gvsv gv gelem |
| 449 | .Ve |
| 450 | .Sp |
| 451 | .Vb 1 |
| 452 | \& padsv padav padhv padany |
| 453 | .Ve |
| 454 | .Sp |
| 455 | .Vb 1 |
| 456 | \& rv2gv refgen srefgen ref |
| 457 | .Ve |
| 458 | .Sp |
| 459 | .Vb 1 |
| 460 | \& bless -- could be used to change ownership of objects (reblessing) |
| 461 | .Ve |
| 462 | .Sp |
| 463 | .Vb 1 |
| 464 | \& pushre regcmaybe regcreset regcomp subst substcont |
| 465 | .Ve |
| 466 | .Sp |
| 467 | .Vb 1 |
| 468 | \& sprintf prtf -- can core dump |
| 469 | .Ve |
| 470 | .Sp |
| 471 | .Vb 1 |
| 472 | \& crypt |
| 473 | .Ve |
| 474 | .Sp |
| 475 | .Vb 1 |
| 476 | \& tie untie |
| 477 | .Ve |
| 478 | .Sp |
| 479 | .Vb 3 |
| 480 | \& dbmopen dbmclose |
| 481 | \& sselect select |
| 482 | \& pipe_op sockpair |
| 483 | .Ve |
| 484 | .Sp |
| 485 | .Vb 1 |
| 486 | \& getppid getpgrp setpgrp getpriority setpriority localtime gmtime |
| 487 | .Ve |
| 488 | .Sp |
| 489 | .Vb 1 |
| 490 | \& entertry leavetry -- can be used to 'hide' fatal errors |
| 491 | .Ve |
| 492 | .Sp |
| 493 | .Vb 1 |
| 494 | \& custom -- where should this go |
| 495 | .Ve |
| 496 | .IP ":base_math" 5 |
| 497 | .IX Item ":base_math" |
| 498 | These ops are not included in :base_core because of the risk of them being |
| 499 | used to generate floating point exceptions (which would have to be caught |
| 500 | using a \f(CW$SIG\fR{\s-1FPE\s0} handler). |
| 501 | .Sp |
| 502 | .Vb 1 |
| 503 | \& atan2 sin cos exp log sqrt |
| 504 | .Ve |
| 505 | .Sp |
| 506 | These ops are not included in :base_core because they have an effect |
| 507 | beyond the scope of the compartment. |
| 508 | .Sp |
| 509 | .Vb 1 |
| 510 | \& rand srand |
| 511 | .Ve |
| 512 | .IP ":base_thread" 5 |
| 513 | .IX Item ":base_thread" |
| 514 | These ops are related to multi\-threading. |
| 515 | .Sp |
| 516 | .Vb 1 |
| 517 | \& lock threadsv |
| 518 | .Ve |
| 519 | .IP ":default" 5 |
| 520 | .IX Item ":default" |
| 521 | A handy tag name for a \fIreasonable\fR default set of ops. (The current ops |
| 522 | allowed are unstable while development continues. It will change.) |
| 523 | .Sp |
| 524 | .Vb 1 |
| 525 | \& :base_core :base_mem :base_loop :base_io :base_orig :base_thread |
| 526 | .Ve |
| 527 | .Sp |
| 528 | If safety matters to you (and why else would you be using the Opcode module?) |
| 529 | then you should not rely on the definition of this, or indeed any other, optag! |
| 530 | .IP ":filesys_read" 5 |
| 531 | .IX Item ":filesys_read" |
| 532 | .Vb 1 |
| 533 | \& stat lstat readlink |
| 534 | .Ve |
| 535 | .Sp |
| 536 | .Vb 3 |
| 537 | \& ftatime ftblk ftchr ftctime ftdir fteexec fteowned fteread |
| 538 | \& ftewrite ftfile ftis ftlink ftmtime ftpipe ftrexec ftrowned |
| 539 | \& ftrread ftsgid ftsize ftsock ftsuid fttty ftzero ftrwrite ftsvtx |
| 540 | .Ve |
| 541 | .Sp |
| 542 | .Vb 1 |
| 543 | \& fttext ftbinary |
| 544 | .Ve |
| 545 | .Sp |
| 546 | .Vb 1 |
| 547 | \& fileno |
| 548 | .Ve |
| 549 | .IP ":sys_db" 5 |
| 550 | .IX Item ":sys_db" |
| 551 | .Vb 4 |
| 552 | \& ghbyname ghbyaddr ghostent shostent ehostent -- hosts |
| 553 | \& gnbyname gnbyaddr gnetent snetent enetent -- networks |
| 554 | \& gpbyname gpbynumber gprotoent sprotoent eprotoent -- protocols |
| 555 | \& gsbyname gsbyport gservent sservent eservent -- services |
| 556 | .Ve |
| 557 | .Sp |
| 558 | .Vb 2 |
| 559 | \& gpwnam gpwuid gpwent spwent epwent getlogin -- users |
| 560 | \& ggrnam ggrgid ggrent sgrent egrent -- groups |
| 561 | .Ve |
| 562 | .IP ":browse" 5 |
| 563 | .IX Item ":browse" |
| 564 | A handy tag name for a \fIreasonable\fR default set of ops beyond the |
| 565 | :default optag. Like :default (and indeed all the other optags) its |
| 566 | current definition is unstable while development continues. It will change. |
| 567 | .Sp |
| 568 | The :browse tag represents the next step beyond :default. It it a |
| 569 | superset of the :default ops and adds :filesys_read the :sys_db. |
| 570 | The intent being that scripts can access more (possibly sensitive) |
| 571 | information about your system but not be able to change it. |
| 572 | .Sp |
| 573 | .Vb 1 |
| 574 | \& :default :filesys_read :sys_db |
| 575 | .Ve |
| 576 | .IP ":filesys_open" 5 |
| 577 | .IX Item ":filesys_open" |
| 578 | .Vb 2 |
| 579 | \& sysopen open close |
| 580 | \& umask binmode |
| 581 | .Ve |
| 582 | .Sp |
| 583 | .Vb 1 |
| 584 | \& open_dir closedir -- other dir ops are in :base_io |
| 585 | .Ve |
| 586 | .IP ":filesys_write" 5 |
| 587 | .IX Item ":filesys_write" |
| 588 | .Vb 1 |
| 589 | \& link unlink rename symlink truncate |
| 590 | .Ve |
| 591 | .Sp |
| 592 | .Vb 1 |
| 593 | \& mkdir rmdir |
| 594 | .Ve |
| 595 | .Sp |
| 596 | .Vb 1 |
| 597 | \& utime chmod chown |
| 598 | .Ve |
| 599 | .Sp |
| 600 | .Vb 1 |
| 601 | \& fcntl -- not strictly filesys related, but possibly as dangerous? |
| 602 | .Ve |
| 603 | .IP ":subprocess" 5 |
| 604 | .IX Item ":subprocess" |
| 605 | .Vb 1 |
| 606 | \& backtick system |
| 607 | .Ve |
| 608 | .Sp |
| 609 | .Vb 1 |
| 610 | \& fork |
| 611 | .Ve |
| 612 | .Sp |
| 613 | .Vb 1 |
| 614 | \& wait waitpid |
| 615 | .Ve |
| 616 | .Sp |
| 617 | .Vb 1 |
| 618 | \& glob -- access to Cshell via <`rm *`> |
| 619 | .Ve |
| 620 | .IP ":ownprocess" 5 |
| 621 | .IX Item ":ownprocess" |
| 622 | .Vb 1 |
| 623 | \& exec exit kill |
| 624 | .Ve |
| 625 | .Sp |
| 626 | .Vb 1 |
| 627 | \& time tms -- could be used for timing attacks (paranoid?) |
| 628 | .Ve |
| 629 | .IP ":others" 5 |
| 630 | .IX Item ":others" |
| 631 | This tag holds groups of assorted specialist opcodes that don't warrant |
| 632 | having optags defined for them. |
| 633 | .Sp |
| 634 | SystemV Interprocess Communications: |
| 635 | .Sp |
| 636 | .Vb 1 |
| 637 | \& msgctl msgget msgrcv msgsnd |
| 638 | .Ve |
| 639 | .Sp |
| 640 | .Vb 1 |
| 641 | \& semctl semget semop |
| 642 | .Ve |
| 643 | .Sp |
| 644 | .Vb 1 |
| 645 | \& shmctl shmget shmread shmwrite |
| 646 | .Ve |
| 647 | .IP ":still_to_be_decided" 5 |
| 648 | .IX Item ":still_to_be_decided" |
| 649 | .Vb 2 |
| 650 | \& chdir |
| 651 | \& flock ioctl |
| 652 | .Ve |
| 653 | .Sp |
| 654 | .Vb 2 |
| 655 | \& socket getpeername ssockopt |
| 656 | \& bind connect listen accept shutdown gsockopt getsockname |
| 657 | .Ve |
| 658 | .Sp |
| 659 | .Vb 4 |
| 660 | \& sleep alarm -- changes global timer state and signal handling |
| 661 | \& sort -- assorted problems including core dumps |
| 662 | \& tied -- can be used to access object implementing a tie |
| 663 | \& pack unpack -- can be used to create/use memory pointers |
| 664 | .Ve |
| 665 | .Sp |
| 666 | .Vb 2 |
| 667 | \& entereval -- can be used to hide code from initial compile |
| 668 | \& require dofile |
| 669 | .Ve |
| 670 | .Sp |
| 671 | .Vb 1 |
| 672 | \& caller -- get info about calling environment and args |
| 673 | .Ve |
| 674 | .Sp |
| 675 | .Vb 1 |
| 676 | \& reset |
| 677 | .Ve |
| 678 | .Sp |
| 679 | .Vb 1 |
| 680 | \& dbstate -- perl -d version of nextstate(ment) opcode |
| 681 | .Ve |
| 682 | .IP ":dangerous" 5 |
| 683 | .IX Item ":dangerous" |
| 684 | This tag is simply a bucket for opcodes that are unlikely to be used via |
| 685 | a tag name but need to be tagged for completeness and documentation. |
| 686 | .Sp |
| 687 | .Vb 1 |
| 688 | \& syscall dump chroot |
| 689 | .Ve |
| 690 | .SH "SEE ALSO" |
| 691 | .IX Header "SEE ALSO" |
| 692 | \&\fIops\fR\|(3) \*(-- perl pragma interface to Opcode module. |
| 693 | .PP |
| 694 | \&\fISafe\fR\|(3) \*(-- Opcode and namespace limited execution compartments |
| 695 | .SH "AUTHORS" |
| 696 | .IX Header "AUTHORS" |
| 697 | Originally designed and implemented by Malcolm Beattie, |
| 698 | mbeattie@sable.ox.ac.uk as part of Safe version 1. |
| 699 | .PP |
| 700 | Split out from Safe module version 1, named opcode tags and other |
| 701 | changes added by Tim Bunce. |