src/env_parallel.pod

   1 #!/usr/bin/perl -w
   2
   3 # SPDX-FileCopyrightText: 2021 Ole Tange, http://ole.tange.dk and Free Software and Foundation, Inc.
   4 # SPDX-License-Identifier: GFDL-1.3-or-later
   5 # SPDX-License-Identifier: CC-BY-SA-4.0
   6
   7 =encoding utf8
   8
   9 =head1 NAME
  10
  11 env_parallel - export environment to GNU parallel
  12
  13
  14 =head1 SYNOPSIS
  15
  16 B<env_parallel> [--record-env|--session|--end-session]
  17   [options for GNU Parallel]
  18
  19
  20 =head1 DESCRIPTION
  21
  22 B<env_parallel> is a shell function that exports the current
  23 environment to GNU B<parallel>.
  24
  25 If the shell function is not loaded, a dummy script will be run
  26 instead that explains how to install the function.
  27
  28 B<env_parallel> is 100 ms slower at startup than pure GNU
  29 B<parallel>, and takes up to 30% longer to start a job (typically 15 ms).
  30
  31 Due to the problem with environment space (see below) the recommended
  32 usage is either:
  33
  34   # Do --record-env into $PARALLEL_IGNORED_NAMES
  35   env_parallel --session
  36
  37   # Define whatever you want to use
  38   myfunc() { myalias and functions $myvar work. $1.; }
  39   alias myalias='echo Aliases'
  40   myvar='and variables'
  41
  42   # env_parallel will not export names in $PARALLEL_IGNORED_NAMES
  43   env_parallel -S localhost myfunc ::: Hooray
  44
  45 Or:
  46
  47   # Record the "clean" environment (this only needs to be run once)
  48   env_parallel --record-env
  49
  50   # Optionally edit ~/.parallel/ignored_vars (only needed once)
  51
  52   # Define whatever you want to use
  53   myfunc() { myalias and functions $myvar work. $1.; }
  54   alias myalias='echo Aliases'
  55   myvar='and variables'
  56
  57   # Use --env _ to only transfer the names not in the "empty" environment
  58   env_parallel --env _ -S localhost myfunc ::: Hooray
  59
  60 In B<csh> B<--session> is not supported:
  61
  62   # Record the "clean" environment - this only needs to be run once
  63   env_parallel --record-env
  64
  65   # Optionally edit ~/.parallel/ignored_vars - only needed once
  66
  67   # Define whatever you want to use
  68   alias myalias 'echo Aliases $myvar \!*.'
  69   set myvar='and variables'
  70
  71   # Use --env _ to only transfer the names not in the "empty" environment
  72   env_parallel --env _ -S localhost myalias ::: work
  73
  74 =head2 Environment space
  75
  76 By default B<env_parallel> will export all environment variables,
  77 arrays, aliases, functions and shell options (see details for the
  78 individual shells below).
  79
  80 But this only works if the size of the current environment is smaller
  81 than the maximal length of a command and smaller than half of the max
  82 if running remotely. E.g. The max size of Bash's command is 128 KB, so
  83 B<env_parallel> will fail if 'B<set | wc -c>' is bigger than 128
  84 KB. Technically the limit is in execve(1) which IPC::open3 uses.
  85
  86 Bash completion functions are well-known for taking up well over 128
  87 KB of environment space and the primary reason for causing
  88 B<env_parallel> to fail.
  89
  90 Instead you can use B<--env> to specify which variables, arrays,
  91 aliases and functions to export as this will only export those with
  92 the given name. Or follow the recommended usage in shown in
  93 DESCRIPTION.
  94
  95
  96 =head1 OPTIONS
  97
  98 Same as GNU B<parallel> in addition to these:
  99
 100 =over 4
 101
 102 =item B<--end-session>
 103
 104 Undo last B<--session>
 105
 106
 107 =item B<--record-env>
 108
 109 Record all names currently defined to be ignored every time running
 110 B<env_parallel> in the future.
 111
 112
 113 =item B<--session>
 114
 115 Ignore all names currently defined. Aliases, variables, arrays, and
 116 functions currently defined will not be transferred.
 117
 118 But names defined I<after> running B<parallel --session> I<will> be
 119 transferred.
 120
 121 This is only valid in the running shell, and can be undone with
 122 B<parallel --end-session>.
 123
 124 You can run multiple B<--session> inside each other:
 125
 126   env_parallel --session
 127   var=not
 128   # var is transferred
 129   env_parallel -Slocalhost 'echo var is $var' ::: ignored
 130   env_parallel --session
 131   # var is not transferred
 132   env_parallel -Slocalhost 'echo var is $var' ::: ignored
 133   env_parallel --end-session
 134   # var is transferred again
 135   env_parallel -Slocalhost 'echo var is $var' ::: ignored
 136
 137
 138
 139 =back
 140
 141
 142 =head1 SUPPORTED SHELLS
 143
 144 =head2 Ash
 145
 146 =head3 Installation
 147
 148 Put this in $HOME/.profile:
 149
 150   . `which env_parallel.ash`
 151
 152 E.g. by doing:
 153
 154   echo '. `which env_parallel.ash`' >> $HOME/.profile
 155
 156 =head3 Supported use
 157
 158 B<--env> is supported to export only the variable, or alias with the
 159 given name. Multiple B<--env>s can be given.
 160
 161 B<--session> is supported.
 162
 163 =over 8
 164
 165 =item aliases
 166
 167   alias myecho='echo aliases'
 168   env_parallel myecho ::: work
 169   env_parallel -S server myecho ::: work
 170   env_parallel --env myecho myecho ::: work
 171   env_parallel --env myecho -S server myecho ::: work
 172
 173   alias multiline='echo multiline
 174     echo aliases'
 175   env_parallel multiline ::: work
 176   env_parallel -S server multiline ::: work
 177   env_parallel --env multiline multiline ::: work
 178   env_parallel --env multiline -S server multiline ::: work
 179
 180 =item functions
 181
 182   ash cannot list defined functions - thus is not supported.
 183
 184 =item variables
 185
 186   myvar=variables
 187   env_parallel echo '$myvar' ::: work
 188   env_parallel -S server echo '$myvar' ::: work
 189   env_parallel --env myvar echo '$myvar' ::: work
 190   env_parallel --env myvar -S server echo '$myvar' ::: work
 191
 192 =item arrays
 193
 194 Arrays are not supported by Ash.
 195
 196 =back
 197
 198 =head2 Bash
 199
 200 =head3 Installation
 201
 202 Put this in $HOME/.bashrc:
 203
 204   . `which env_parallel.bash`
 205
 206 E.g. by doing:
 207
 208   echo '. `which env_parallel.bash`' >> $HOME/.bashrc
 209
 210 =head3 Supported use
 211
 212 B<--env> is supported to export only the variable, alias, function, or
 213 array with the given name. Multiple B<--env>s can be given.
 214
 215 B<--session> is supported.
 216
 217 =over 8
 218
 219 =item aliases
 220
 221   alias myecho='echo aliases'
 222   env_parallel myecho ::: work
 223   env_parallel -S server myecho ::: work
 224   env_parallel --env myecho myecho ::: work
 225   env_parallel --env myecho -S server myecho ::: work
 226
 227   alias multiline='echo multiline
 228     echo aliases'
 229   env_parallel 'multiline {};
 230     echo but only when followed by a newline' ::: work
 231   env_parallel -S server 'multiline {};
 232     echo but only when followed by a newline' ::: work
 233   env_parallel --env multiline 'multiline {};
 234     echo but only when followed by a newline' ::: work
 235   env_parallel --env multiline -S server 'multiline {};
 236     echo but only when followed by a newline' ::: work
 237
 238 =item functions
 239
 240   myfunc() { echo functions $*; }
 241   env_parallel myfunc ::: work
 242   env_parallel -S server myfunc ::: work
 243   env_parallel --env myfunc myfunc ::: work
 244   env_parallel --env myfunc -S server myfunc ::: work
 245
 246 =item variables
 247
 248   myvar=variables
 249   env_parallel echo '$myvar' ::: work
 250   env_parallel -S server echo '$myvar' ::: work
 251   env_parallel --env myvar echo '$myvar' ::: work
 252   env_parallel --env myvar -S server echo '$myvar' ::: work
 253
 254 =item arrays
 255
 256   myarray=(arrays work, too)
 257   env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
 258   env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
 259   env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
 260   env_parallel -k --env myarray -S server \
 261     echo '${myarray[{}]}' ::: 0 1 2
 262
 263 =back
 264
 265 =head3 BUGS
 266
 267 Due to a bug in Bash, aliases containing newlines must be followed by
 268 a newline in the command. Some systems are not affected by this bug,
 269 but will print a warning anyway.
 270
 271 =head2 csh
 272
 273 B<env_parallel> for B<csh> breaks B<$PARALLEL>, so do not use
 274 B<$PARALLEL>.
 275
 276 =head3 Installation
 277
 278 Put this in $HOME/.cshrc:
 279
 280   source `which env_parallel.csh`
 281
 282 E.g. by doing:
 283
 284   echo 'source `which env_parallel.csh`' >> $HOME/.cshrc
 285
 286 =head3 Supported use
 287
 288 B<--env> is supported to export only the variable, alias, or
 289 array with the given name. Multiple B<--env>s can be given.
 290
 291 =over 8
 292
 293 =item aliases
 294
 295   alias myecho 'echo aliases'
 296   env_parallel myecho ::: work
 297   env_parallel -S server myecho ::: work
 298   env_parallel --env myecho myecho ::: work
 299   env_parallel --env myecho -S server myecho ::: work
 300
 301 =item functions
 302
 303 Not supported by B<csh>.
 304
 305 =item variables
 306
 307   set myvar=variables
 308   env_parallel echo '$myvar' ::: work
 309   env_parallel -S server echo '$myvar' ::: work
 310   env_parallel --env myvar echo '$myvar' ::: work
 311   env_parallel --env myvar -S server echo '$myvar' ::: work
 312
 313 =item arrays with no special chars
 314
 315   set myarray=(arrays work, too)
 316   env_parallel -k echo \$'{myarray[{}]}' ::: 1 2 3
 317   env_parallel -k -S server echo \$'{myarray[{}]}' ::: 1 2 3
 318   env_parallel -k --env myarray echo \$'{myarray[{}]}' ::: 1 2 3
 319   env_parallel -k --env myarray -S server \
 320     echo \$'{myarray[{}]}' ::: 1 2 3
 321
 322 =back
 323
 324
 325 =head2 Dash
 326
 327 =head3 Installation
 328
 329 Put this in $HOME/.profile:
 330
 331   . `which env_parallel.dash`
 332
 333 E.g. by doing:
 334
 335   echo '. `which env_parallel.dash`' >> $HOME/.profile
 336
 337 =head3 Supported use
 338
 339 B<--env> is supported to export only the variable, or alias with the
 340 given name. Multiple B<--env>s can be given.
 341
 342 B<--session> is supported.
 343
 344 =over 8
 345
 346 =item aliases
 347
 348   alias myecho='echo aliases'
 349   env_parallel myecho ::: work
 350   env_parallel -S server myecho ::: work
 351   env_parallel --env myecho myecho ::: work
 352   env_parallel --env myecho -S server myecho ::: work
 353
 354   alias multiline='echo multiline
 355     echo aliases'
 356   env_parallel multiline ::: work
 357   env_parallel -S server multiline ::: work
 358   env_parallel --env multiline multiline ::: work
 359   env_parallel --env multiline -S server multiline ::: work
 360
 361 =item functions
 362
 363   dash cannot list defined functions - thus is not supported.
 364
 365 =item variables
 366
 367   myvar=variables
 368   env_parallel echo '$myvar' ::: work
 369   env_parallel -S server echo '$myvar' ::: work
 370   env_parallel --env myvar echo '$myvar' ::: work
 371   env_parallel --env myvar -S server echo '$myvar' ::: work
 372
 373 =item arrays
 374
 375   dash does not support arrays.
 376
 377 =back
 378
 379
 380 =head2 fish
 381
 382 =head3 Installation
 383
 384 Put this in $HOME/.config/fish/config.fish:
 385
 386   source (which env_parallel.fish)
 387
 388 E.g. by doing:
 389
 390   echo 'source (which env_parallel.fish)' \
 391     >> $HOME/.config/fish/config.fish
 392
 393 =head3 Supported use
 394
 395 B<--env> is supported to export only the variable, alias, function, or
 396 array with the given name. Multiple B<--env>s can be given.
 397
 398 B<--session> is supported.
 399
 400 =over 8
 401
 402 =item aliases
 403
 404   alias myecho 'echo aliases'
 405   env_parallel myecho ::: work
 406   env_parallel -S server myecho ::: work
 407   env_parallel --env myecho myecho ::: work
 408   env_parallel --env myecho -S server myecho ::: work
 409
 410 =item functions
 411
 412   function myfunc
 413     echo functions $argv
 414   end
 415   env_parallel myfunc ::: work
 416   env_parallel -S server myfunc ::: work
 417   env_parallel --env myfunc myfunc ::: work
 418   env_parallel --env myfunc -S server myfunc ::: work
 419
 420 =item variables
 421
 422   set myvar variables
 423   env_parallel echo '$myvar' ::: work
 424   env_parallel -S server echo '$myvar' ::: work
 425   env_parallel --env myvar echo '$myvar' ::: work
 426   env_parallel --env myvar -S server echo '$myvar' ::: work
 427
 428 =item arrays
 429
 430   set myarray arrays work, too
 431   env_parallel -k echo '$myarray[{}]' ::: 1 2 3
 432   env_parallel -k -S server echo '$myarray[{}]' ::: 1 2 3
 433   env_parallel -k --env myarray echo '$myarray[{}]' ::: 1 2 3
 434   env_parallel -k --env myarray -S server \
 435     echo '$myarray[{}]' ::: 1 2 3
 436
 437 =back
 438
 439
 440 =head2 ksh
 441
 442 =head3 Installation
 443
 444 Put this in $HOME/.kshrc:
 445
 446   source `which env_parallel.ksh`
 447
 448 E.g. by doing:
 449
 450   echo 'source `which env_parallel.ksh`' >> $HOME/.kshrc
 451
 452 =head3 Supported use
 453
 454 B<--env> is supported to export only the variable, alias, function, or
 455 array with the given name. Multiple B<--env>s can be given.
 456
 457 B<--session> is supported.
 458
 459 =over 8
 460
 461 =item aliases
 462
 463   alias myecho='echo aliases'
 464   env_parallel myecho ::: work
 465   env_parallel -S server myecho ::: work
 466   env_parallel --env myecho myecho ::: work
 467   env_parallel --env myecho -S server myecho ::: work
 468
 469   alias multiline='echo multiline
 470     echo aliases'
 471   env_parallel multiline ::: work
 472   env_parallel -S server multiline ::: work
 473   env_parallel --env multiline multiline ::: work
 474   env_parallel --env multiline -S server multiline ::: work
 475
 476 =item functions
 477
 478   myfunc() { echo functions $*; }
 479   env_parallel myfunc ::: work
 480   env_parallel -S server myfunc ::: work
 481   env_parallel --env myfunc myfunc ::: work
 482   env_parallel --env myfunc -S server myfunc ::: work
 483
 484 =item variables
 485
 486   myvar=variables
 487   env_parallel echo '$myvar' ::: work
 488   env_parallel -S server echo '$myvar' ::: work
 489   env_parallel --env myvar echo '$myvar' ::: work
 490   env_parallel --env myvar -S server echo '$myvar' ::: work
 491
 492 =item arrays
 493
 494   myarray=(arrays work, too)
 495   env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
 496   env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
 497   env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
 498   env_parallel -k --env myarray -S server \
 499     echo '${myarray[{}]}' ::: 0 1 2
 500
 501 =back
 502
 503
 504 =head2 mksh
 505
 506 =head3 Installation
 507
 508 Put this in $HOME/.mkshrc:
 509
 510   source `which env_parallel.mksh`
 511
 512 E.g. by doing:
 513
 514   echo 'source `which env_parallel.mksh`' >> $HOME/.mkshrc
 515
 516 =head3 Supported use
 517
 518 B<--env> is supported to export only the variable, alias, function, or
 519 array with the given name. Multiple B<--env>s can be given.
 520
 521 B<--session> is supported.
 522
 523 =over 8
 524
 525 =item aliases
 526
 527   alias myecho='echo aliases'
 528   env_parallel myecho ::: work
 529   env_parallel -S server myecho ::: work
 530   env_parallel --env myecho myecho ::: work
 531   env_parallel --env myecho -S server myecho ::: work
 532
 533   alias multiline='echo multiline
 534     echo aliases'
 535   env_parallel multiline ::: work
 536   env_parallel -S server multiline ::: work
 537   env_parallel --env multiline multiline ::: work
 538   env_parallel --env multiline -S server multiline ::: work
 539
 540 =item functions
 541
 542   myfunc() { echo functions $*; }
 543   env_parallel myfunc ::: work
 544   env_parallel -S server myfunc ::: work
 545   env_parallel --env myfunc myfunc ::: work
 546   env_parallel --env myfunc -S server myfunc ::: work
 547
 548 =item variables
 549
 550   myvar=variables
 551   env_parallel echo '$myvar' ::: work
 552   env_parallel -S server echo '$myvar' ::: work
 553   env_parallel --env myvar echo '$myvar' ::: work
 554   env_parallel --env myvar -S server echo '$myvar' ::: work
 555
 556 =item arrays
 557
 558   myarray=(arrays work, too)
 559   env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
 560   env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
 561   env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
 562   env_parallel -k --env myarray -S server \
 563     echo '${myarray[{}]}' ::: 0 1 2
 564
 565 =back
 566
 567
 568 =head2 pdksh
 569
 570 =head3 Installation
 571
 572 Put this in $HOME/.profile:
 573
 574   source `which env_parallel.pdksh`
 575
 576 E.g. by doing:
 577
 578   echo 'source `which env_parallel.pdksh`' >> $HOME/.profile
 579
 580 =head3 Supported use
 581
 582 B<--env> is supported to export only the variable, alias, function, or
 583 array with the given name. Multiple B<--env>s can be given.
 584
 585 B<--session> is supported.
 586
 587 =over 8
 588
 589 =item aliases
 590
 591   alias myecho="echo aliases";
 592   env_parallel myecho ::: work;
 593   env_parallel -S server myecho ::: work;
 594   env_parallel --env myecho myecho ::: work;
 595   env_parallel --env myecho -S server myecho ::: work
 596
 597 =item functions
 598
 599   myfunc() { echo functions $*; };
 600   env_parallel myfunc ::: work;
 601   env_parallel -S server myfunc ::: work;
 602   env_parallel --env myfunc myfunc ::: work;
 603   env_parallel --env myfunc -S server myfunc ::: work
 604
 605 =item variables
 606
 607   myvar=variables;
 608   env_parallel echo "\$myvar" ::: work;
 609   env_parallel -S server echo "\$myvar" ::: work;
 610   env_parallel --env myvar echo "\$myvar" ::: work;
 611   env_parallel --env myvar -S server echo "\$myvar" ::: work
 612
 613 =item arrays
 614
 615   myarray=(arrays work, too);
 616   env_parallel -k echo "\${myarray[{}]}" ::: 0 1 2;
 617   env_parallel -k -S server echo "\${myarray[{}]}" ::: 0 1 2;
 618   env_parallel -k --env myarray echo "\${myarray[{}]}" ::: 0 1 2;
 619   env_parallel -k --env myarray -S server \
 620     echo "\${myarray[{}]}" ::: 0 1 2
 621
 622 =back
 623
 624
 625 =head2 sh
 626
 627 =head3 Installation
 628
 629 Put this in $HOME/.profile:
 630
 631   . `which env_parallel.sh`
 632
 633 E.g. by doing:
 634
 635   echo '. `which env_parallel.sh`' >> $HOME/.profile
 636
 637 =head3 Supported use
 638
 639 B<--env> is supported to export only the variable, or alias with the
 640 given name. Multiple B<--env>s can be given.
 641
 642 B<--session> is supported.
 643
 644 =over 8
 645
 646 =item aliases
 647
 648   sh does not support aliases.
 649
 650 =item functions
 651
 652   myfunc() { echo functions $*; }
 653   env_parallel myfunc ::: work
 654   env_parallel -S server myfunc ::: work
 655   env_parallel --env myfunc myfunc ::: work
 656   env_parallel --env myfunc -S server myfunc ::: work
 657
 658 =item variables
 659
 660   myvar=variables
 661   env_parallel echo '$myvar' ::: work
 662   env_parallel -S server echo '$myvar' ::: work
 663   env_parallel --env myvar echo '$myvar' ::: work
 664   env_parallel --env myvar -S server echo '$myvar' ::: work
 665
 666 =item arrays
 667
 668   sh does not support arrays.
 669
 670 =back
 671
 672
 673 =head2 tcsh
 674
 675 B<env_parallel> for B<tcsh> breaks B<$PARALLEL>, so do not use
 676 B<$PARALLEL>.
 677
 678 =head3 Installation
 679
 680 Put this in $HOME/.tcshrc:
 681
 682   source `which env_parallel.tcsh`
 683
 684 E.g. by doing:
 685
 686   echo 'source `which env_parallel.tcsh`' >> $HOME/.tcshrc
 687
 688 =head3 Supported use
 689
 690 B<--env> is supported to export only the variable, alias, or
 691 array with the given name. Multiple B<--env>s can be given.
 692
 693 =over 8
 694
 695 =item aliases
 696
 697   alias myecho 'echo aliases'
 698   env_parallel myecho ::: work
 699   env_parallel -S server myecho ::: work
 700   env_parallel --env myecho myecho ::: work
 701   env_parallel --env myecho -S server myecho ::: work
 702
 703 =item functions
 704
 705 Not supported by B<tcsh>.
 706
 707 =item variables
 708
 709   set myvar=variables
 710   env_parallel echo '$myvar' ::: work
 711   env_parallel -S server echo '$myvar' ::: work
 712   env_parallel --env myvar echo '$myvar' ::: work
 713   env_parallel --env myvar -S server echo '$myvar' ::: work
 714
 715 =item arrays with no special chars
 716
 717   set myarray=(arrays work, too)
 718   env_parallel -k echo \$'{myarray[{}]}' ::: 1 2 3
 719   env_parallel -k -S server echo \$'{myarray[{}]}' ::: 1 2 3
 720   env_parallel -k --env myarray echo \$'{myarray[{}]}' ::: 1 2 3
 721   env_parallel -k --env myarray -S server \
 722     echo \$'{myarray[{}]}' ::: 1 2 3
 723
 724 =back
 725
 726
 727 =head2 Zsh
 728
 729 =head3 Installation
 730
 731 Put this in $HOME/.zshrc:
 732
 733   . `which env_parallel.zsh`
 734
 735 E.g. by doing:
 736
 737   echo '. `which env_parallel.zsh`' >> $HOME/.zshenv
 738
 739 =head3 Supported use
 740
 741 B<--env> is supported to export only the variable, alias, function, or
 742 array with the given name. Multiple B<--env>s can be given.
 743
 744 B<--session> is supported.
 745
 746 =over 8
 747
 748 =item aliases
 749
 750   alias myecho='echo aliases'
 751   env_parallel myecho ::: work
 752   env_parallel -S server myecho ::: work
 753   env_parallel --env myecho myecho ::: work
 754   env_parallel --env myecho -S server myecho ::: work
 755
 756   alias multiline='echo multiline
 757     echo aliases'
 758   env_parallel multiline ::: work
 759   env_parallel -S server multiline ::: work
 760   env_parallel --env multiline multiline ::: work
 761   env_parallel --env multiline -S server multiline ::: work
 762
 763 =item functions
 764
 765   myfunc() { echo functions $*; }
 766   env_parallel myfunc ::: work
 767   env_parallel -S server myfunc ::: work
 768   env_parallel --env myfunc myfunc ::: work
 769   env_parallel --env myfunc -S server myfunc ::: work
 770
 771 =item variables
 772
 773   myvar=variables
 774   env_parallel echo '$myvar' ::: work
 775   env_parallel -S server echo '$myvar' ::: work
 776   env_parallel --env myvar echo '$myvar' ::: work
 777   env_parallel --env myvar -S server echo '$myvar' ::: work
 778
 779 =item arrays
 780
 781   myarray=(arrays work, too)
 782   env_parallel -k echo '${myarray[{}]}' ::: 1 2 3
 783   env_parallel -k -S server echo '${myarray[{}]}' ::: 1 2 3
 784   env_parallel -k --env myarray echo '${myarray[{}]}' ::: 1 2 3
 785   env_parallel -k --env myarray -S server \
 786     echo '${myarray[{}]}' ::: 1 2 3
 787
 788 =back
 789
 790
 791 =head1 EXIT STATUS
 792
 793 Same as GNU B<parallel>.
 794
 795
 796 =head1 AUTHOR
 797
 798 When using GNU B<env_parallel> for a publication please cite:
 799
 800 O. Tange (2018): GNU Parallel 2018, March 2018, ISBN 9781387509881,
 801 DOI: 10.5281/zenodo.1146014.
 802
 803 This helps funding further development; and it won't cost you a cent.
 804 If you pay 10000 EUR you should feel free to use GNU Parallel without citing.
 805
 806 Copyright (C) 2007-10-18 Ole Tange, http://ole.tange.dk
 807
 808 Copyright (C) 2008-2010 Ole Tange, http://ole.tange.dk
 809
 810 Copyright (C) 2010-2021 Ole Tange, http://ole.tange.dk and Free
 811 Software Foundation, Inc.
 812
 813
 814 =head1 LICENSE
 815
 816 This program is free software; you can redistribute it and/or modify
 817 it under the terms of the GNU General Public License as published by
 818 the Free Software Foundation; either version 3 of the License, or
 819 at your option any later version.
 820
 821 This program is distributed in the hope that it will be useful,
 822 but WITHOUT ANY WARRANTY; without even the implied warranty of
 823 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 824 GNU General Public License for more details.
 825
 826 You should have received a copy of the GNU General Public License
 827 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 828
 829 =head2 Documentation license I
 830
 831 Permission is granted to copy, distribute and/or modify this
 832 documentation under the terms of the GNU Free Documentation License,
 833 Version 1.3 or any later version published by the Free Software
 834 Foundation; with no Invariant Sections, with no Front-Cover Texts, and
 835 with no Back-Cover Texts.  A copy of the license is included in the
 836 file LICENSES/GFDL-1.3-or-later.txt.
 837
 838
 839 =head2 Documentation license II
 840
 841 You are free:
 842
 843 =over 9
 844
 845 =item B<to Share>
 846
 847 to copy, distribute and transmit the work
 848
 849 =item B<to Remix>
 850
 851 to adapt the work
 852
 853 =back
 854
 855 Under the following conditions:
 856
 857 =over 9
 858
 859 =item B<Attribution>
 860
 861 You must attribute the work in the manner specified by the author or
 862 licensor (but not in any way that suggests that they endorse you or
 863 your use of the work).
 864
 865 =item B<Share Alike>
 866
 867 If you alter, transform, or build upon this work, you may distribute
 868 the resulting work only under the same, similar or a compatible
 869 license.
 870
 871 =back
 872
 873 With the understanding that:
 874
 875 =over 9
 876
 877 =item B<Waiver>
 878
 879 Any of the above conditions can be waived if you get permission from
 880 the copyright holder.
 881
 882 =item B<Public Domain>
 883
 884 Where the work or any of its elements is in the public domain under
 885 applicable law, that status is in no way affected by the license.
 886
 887 =item B<Other Rights>
 888
 889 In no way are any of the following rights affected by the license:
 890
 891 =over 2
 892
 893 =item *
 894
 895 Your fair dealing or fair use rights, or other applicable
 896 copyright exceptions and limitations;
 897
 898 =item *
 899
 900 The author's moral rights;
 901
 902 =item *
 903
 904 Rights other persons may have either in the work itself or in
 905 how the work is used, such as publicity or privacy rights.
 906
 907 =back
 908
 909 =back
 910
 911 =over 9
 912
 913 =item B<Notice>
 914
 915 For any reuse or distribution, you must make clear to others the
 916 license terms of this work.
 917
 918 =back
 919
 920 A copy of the full license is included in the file as
 921 LICENCES/CC-BY-SA-4.0.txt
 922
 923
 924 =head1 DEPENDENCIES
 925
 926 B<env_parallel> uses GNU B<parallel>.
 927
 928
 929 =head1 SEE ALSO
 930
 931 B<parallel>(1), B<ash>(1), B<bash>(1), B<csh>(1), B<dash>(1),
 932 B<fish>(1), B<ksh>(1), B<pdksh>(1) B<tcsh>(1), B<zsh>(1).
 933
 934
 935 =cut