src/env_parallel.bash

   1 #!/usr/bin/env bash
   2
   3 # This file must be sourced in sh/ash/dash/bash/ksh/mksh/zsh:
   4 #
   5 #   . env_parallel.sh
   6 #   source env_parallel.ash
   7 #   source env_parallel.dash
   8 #   source env_parallel.bash
   9 #   source env_parallel.ksh
  10 #   source env_parallel.mksh
  11 #   source env_parallel.zsh
  12 #
  13 # after which 'env_parallel' works
  14 #
  15 #
  16 # Copyright (C) 2016-2024 Ole Tange, http://ole.tange.dk and Free
  17 # Software Foundation, Inc.
  18 #
  19 # This program is free software; you can redistribute it and/or modify
  20 # it under the terms of the GNU General Public License as published by
  21 # the Free Software Foundation; either version 3 of the License, or
  22 # (at your option) any later version.
  23 #
  24 # This program is distributed in the hope that it will be useful, but
  25 # WITHOUT ANY WARRANTY; without even the implied warranty of
  26 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  27 # General Public License for more details.
  28 #
  29 # You should have received a copy of the GNU General Public License
  30 # along with this program; if not, see <http://www.gnu.org/licenses/>
  31 # or write to the Free Software Foundation, Inc., 51 Franklin St,
  32 # Fifth Floor, Boston, MA 02110-1301 USA
  33 #
  34 # SPDX-FileCopyrightText: 2021-2024 Ole Tange, http://ole.tange.dk and Free Software and Foundation, Inc.
  35 # SPDX-License-Identifier: GPL-3.0-or-later
  36 # shellcheck disable=SC2006
  37
  38 env_parallel() {
  39     # env_parallel.{sh,ash,dash,bash,ksh,mksh,zsh}
  40
  41     # Check shell dialect
  42     if [ -n "$BASH_VERSION" ]; then
  43         _shell_DIALECT=bash
  44         _eval_needed=false
  45         _prefix_PARALLEL_ENV=_prefix_PARALLEL_ENV_bash
  46     elif [ -n "$ZSH_VERSION" ]; then
  47         _shell_DIALECT=zsh
  48         _eval_needed=true
  49         _prefix_PARALLEL_ENV=false
  50     elif [ -n "$KSH_VERSION" ]; then
  51         _shell_DIALECT=ksh
  52         _eval_needed=false
  53         _prefix_PARALLEL_ENV=false
  54     else
  55         # Dash/ash - can these be detected better?
  56         _shell_DIALECT="sh"
  57         _eval_needed=false
  58         _prefix_PARALLEL_ENV=false
  59     fi
  60     _names_of_ALIASES() {
  61         _names_of_ALIASES_$_shell_DIALECT
  62     }
  63     _names_of_ALIASES_sh() {
  64         # alias fails on Unixware 5
  65         for _i in `alias 2>/dev/null | perl -ne 's/^alias //;s/^(\S+)=.*/$1/ && print' 2>/dev/null`; do
  66             # Check if this name really is an alias
  67             # or just part of a multiline alias definition
  68             if alias "$_i" >/dev/null 2>/dev/null; then
  69                 echo "$_i"
  70             fi
  71         done
  72     }
  73     _names_of_ALIASES_bash() {
  74         # No aliases will return false. This error should be ignored.
  75         # shellcheck disable=SC3044
  76         compgen -a || true
  77     }
  78     _names_of_ALIASES_ksh() {
  79         alias | perl -pe 's/=.*//'
  80     }
  81     _names_of_ALIASES_zsh() {
  82         # shellcheck disable=SC2086,SC2296
  83         print -l ${(k)aliases}
  84     }
  85     _bodies_of_ALIASES() {
  86         _bodies_of_ALIASES_$_shell_DIALECT "$@"
  87     }
  88     _bodies_of_ALIASES_sh() {
  89         # alias may return:
  90         #   myalias='definition' (GNU/Linux ash)
  91         #   alias myalias='definition' (FreeBSD ash)
  92         # so remove 'alias ' from first line
  93         for _i in "$@"; do
  94                 echo 'alias '"`alias "$_i" | perl -pe '1..1 and s/^alias //'`"
  95         done
  96     }
  97     _bodies_of_ALIASES_bash() {
  98         # shellcheck disable=SC3043
  99         local _i
 100         for _i in "$@"; do
 101             # shellcheck disable=SC2046
 102             if [ $(alias "$_i" | wc -l) = 1 ] ; then
 103                 true Alias is a single line. Good.
 104             else
 105                 _warning_PAR "Alias '$_i' contains newline."
 106                 _warning_PAR "Make sure the command has at least one newline after '$_i'."
 107                 _warning_PAR "See BUGS in 'man env_parallel'."
 108             fi
 109         done
 110         alias "$@"
 111     }
 112     _bodies_of_ALIASES_ksh() {
 113         alias "$@" | perl -pe 's/^/alias /;
 114                      sub warning { print STDERR "env_parallel: Warning: @_\n"; }
 115                      if(/^alias (\S+)=\$.*\\n/) {
 116                          warning("Alias \"$1\" contains newline.");
 117                          warning("Make sure the command has at least one newline after \"$1\".");
 118                          warning("See BUGS in \"man env_parallel\".");
 119                      }'
 120
 121     }
 122     _bodies_of_ALIASES_zsh() {
 123         # shellcheck disable=SC3043
 124         local _i
 125         for _i in "$@"; do
 126                 echo 'alias '"$(alias "$_i")"
 127         done
 128     }
 129     _names_of_FUNCTIONS() {
 130         _names_of_FUNCTIONS_$_shell_DIALECT
 131     }
 132     _names_of_FUNCTIONS_bash() {
 133         # shellcheck disable=SC3044
 134         compgen -A function
 135     }
 136     _names_of_maybe_FUNCTIONS() {
 137         set | perl -ne '/^([A-Z_0-9]+)\s*\(\)\s*\{?$/i and print "$1\n"'
 138     }
 139     _names_of_FUNCTIONS_sh() {
 140         # myfunc is a function
 141         # shellcheck disable=SC2046
 142         LANG=C type `_names_of_maybe_FUNCTIONS` |
 143             perl -ne '/^(\S+) is a function$/ and not $seen{$1}++ and print "$1\n"'
 144     }
 145     _names_of_FUNCTIONS_ksh() {
 146         # shellcheck disable=SC3044
 147         typeset +f | perl -pe 's/\(\).*//; s/ .*//;'
 148     }
 149     _names_of_FUNCTIONS_zsh() {
 150         # shellcheck disable=SC2086,SC2296
 151         print -l ${(k)functions}
 152     }
 153     _bodies_of_FUNCTIONS() {
 154         _bodies_of_FUNCTIONS_$_shell_DIALECT "$@"
 155     }
 156     _bodies_of_FUNCTIONS_sh() {
 157         LANG=C type "$@" | perl -ne '/^(\S+) is a function$/ or print'
 158     }
 159     _bodies_of_FUNCTIONS_bash() {
 160         # shellcheck disable=SC3044
 161         typeset -f "$@"
 162     }
 163     _bodies_of_FUNCTIONS_ksh() {
 164         functions "$@"
 165     }
 166     _bodies_of_FUNCTIONS_zsh() {
 167         # shellcheck disable=SC3044
 168         typeset -f "$@"
 169     }
 170     _names_of_VARIABLES() {
 171         _names_of_VARIABLES_$_shell_DIALECT
 172     }
 173     _names_of_VARIABLES_sh() {
 174         # This may screw up if variables contain \n and =
 175         set | perl -ne 's/^(\S+?)=.*/$1/ and print;'
 176     }
 177     _names_of_VARIABLES_bash() {
 178         # shellcheck disable=SC3044
 179         compgen -A variable
 180     }
 181     _names_of_VARIABLES_ksh() {
 182         # mksh: typeset +p |
 183         #    perl -pe 's/^(type)?set( [-+][a-zA-Z0-9]*)* //; s/(\[\d+\])?=.*//' |
 184         #    uniq
 185         # ksh: typeset +p | perl -pe 's/^typeset .. //'
 186         # shellcheck disable=SC3044
 187         typeset +p |
 188             perl -pe 's/^(type)?set( [-+][a-zA-Z0-9]*)* //; s/(\[\d+\])?=.*//' |
 189             uniq
 190     }
 191     _names_of_VARIABLES_zsh() {
 192         # shellcheck disable=SC2086,SC2296
 193         print -l ${(k)parameters}
 194     }
 195     _bodies_of_VARIABLES() {
 196         _bodies_of_VARIABLES_$_shell_DIALECT "$@"
 197     }
 198     _bodies_of_VARIABLES_sh() {
 199         # Crappy typeset -p
 200         for _i in "$@"
 201         do
 202             perl -e 'print @ARGV' "$_i="
 203             eval echo "\"\$$_i\"" | perl -e '$/=undef; $a=<>; chop($a); print $a' |
 204                 perl -pe 's/[\002-\011\013-\032\\\#\?\`\(\)\{\}\[\]\^\*\<\=\>\~\|\; \"\!\$\&\202-\377]/\\$&/go;'"s/'/\\\'/g; s/[\n]/'\\n'/go;";
 205             echo
 206         done
 207     }
 208     _bodies_of_VARIABLES_bash() {
 209         # shellcheck disable=SC3044
 210         typeset -p "$@"
 211     }
 212     _bodies_of_VARIABLES_ksh() {
 213         # shellcheck disable=SC3044
 214         typeset -p "$@"
 215     }
 216     _bodies_of_VARIABLES_zsh() {
 217         # shellcheck disable=SC3044
 218         typeset -p "$@"
 219     }
 220     _ignore_HARDCODED() {
 221         _ignore_HARDCODED_$_shell_DIALECT
 222     }
 223     _ignore_HARDCODED_sh() {
 224         # These names cannot be detected
 225         echo '(_|TIMEOUT|IFS)'
 226     }
 227     _ignore_HARDCODED_bash() {
 228         # Copying $RANDOM will cause it not to be random
 229         # The rest cannot be detected as read-only
 230         echo '(RANDOM|_|TIMEOUT|GROUPS|FUNCNAME|DIRSTACK|PIPESTATUS|USERNAME|BASHPID|BASH_[A-Z_]+)'
 231     }
 232     _ignore_HARDCODED_ksh() {
 233         # These names cannot be detected
 234         echo '(_|TIMEOUT|IFS)'
 235     }
 236     _ignore_HARDCODED_zsh() {
 237         # These names cannot be detected
 238         echo '([-\?\#\!\$\*\@\_0]|zsh_eval_context|ZSH_EVAL_CONTEXT|LINENO|IFS|commands|functions|options|aliases|EUID|EGID|UID|GID|dis_patchars|patchars|terminfo|galiases|keymaps|parameters|jobdirs|dirstack|functrace|funcsourcetrace|zsh_scheduled_events|dis_aliases|dis_reswords|dis_saliases|modules|reswords|saliases|widgets|userdirs|historywords|nameddirs|termcap|dis_builtins|dis_functions|jobtexts|funcfiletrace|dis_galiases|builtins|history|jobstates|funcstack|run-help)'
 239     }
 240     _ignore_READONLY() {
 241         _ignore_READONLY_$_shell_DIALECT
 242     }
 243     _parse_READONLY() {
 244         # shellcheck disable=SC1078,SC1079,SC2026
 245         perl -e '@r = map {
 246                 chomp;
 247                 # sh on UnixWare: readonly TIMEOUT
 248                 # ash: readonly var='val'
 249                 # ksh: var='val'
 250                 # mksh: PIPESTATUS[0]
 251                 s/^(readonly )?([^=\[ ]*?)(\[\d+\])?(=.*|)$/$2/ or
 252                 # bash: declare -ar BASH_VERSINFO=([0]="4" [1]="4")
 253                 # zsh: typeset -r var='val'
 254                   s/^\S+\s+\S+\s+(\S[^=]*)(=.*|$)/$1/;
 255                 $_ } <>;
 256             $vars = join "|",map { quotemeta $_ } @r;
 257             print $vars ? "($vars)" : "(,,nO,,VaRs,,)";
 258             '
 259     }
 260     _ignore_READONLY_sh() {
 261         readonly | _parse_READONLY
 262     }
 263     _ignore_READONLY_bash() {
 264         readonly | _parse_READONLY
 265     }
 266     _ignore_READONLY_ksh() {
 267         readonly | _parse_READONLY
 268     }
 269     _ignore_READONLY_zsh() {
 270         # shellcheck disable=SC3044
 271         typeset -pr | _parse_READONLY
 272     }
 273     _remove_bad_NAMES() {
 274         # Do not transfer vars and funcs from env_parallel
 275         # shellcheck disable=SC2006
 276         _ignore_RO="`_ignore_READONLY`"
 277         # shellcheck disable=SC2006
 278         _ignore_HARD="`_ignore_HARDCODED`"
 279         # To avoid depending on grep dialect, use Perl version of:
 280         # grep -Ev '^(...)$' |
 281         perl -ne '/^(
 282                      PARALLEL_ENV|
 283                      PARALLEL_TMP|
 284                      _alias_NAMES|
 285                      _bodies_of_ALIASES|
 286                      _bodies_of_FUNCTIONS|
 287                      _bodies_of_VARIABLES|
 288                      _error_PAR|
 289                      _function_NAMES|
 290                      _get_ignored_VARS|
 291                      _grep_REGEXP|
 292                      _ignore_HARD|
 293                      _ignore_HARDCODED|
 294                      _ignore_READONLY|
 295                      _ignore_RO|
 296                      _ignore_UNDERSCORE|
 297                      _list_alias_BODIES|
 298                      _list_function_BODIES|
 299                      _list_variable_VALUES|
 300                      _make_grep_REGEXP|
 301                      _names_of_ALIASES|
 302                      _names_of_FUNCTIONS|
 303                      _names_of_VARIABLES|
 304                      _names_of_maybe_FUNCTIONS|
 305                      _parallel_exit_CODE|
 306                      _prefix_PARALLEL_ENV|
 307                      _prefix_PARALLEL_ENV_bash|
 308                      _remove_bad_NAMES|
 309                      _remove_readonly|
 310                      _variable_NAMES|
 311                      _warning_PAR|
 312                      _which_PAR)$/x and next;
 313             # Filter names matching --env
 314             /^'"$_grep_REGEXP"'$/ or next;
 315             /^'"$_ignore_UNDERSCORE"'$/ and next;
 316             # Remove readonly variables
 317             /^'"$_ignore_RO"'$/ and next;
 318             /^'"$_ignore_HARD"'$/ and next;
 319             print;'
 320     }
 321     _prefix_PARALLEL_ENV_bash() {
 322         # shellcheck disable=SC3044
 323         shopt 2>/dev/null |
 324         perl -pe 's:\s+off:;: and s/^/shopt -u /;
 325                   s:\s+on:;: and s/^/shopt -s /;
 326                   s:;$:&>/dev/null;:';
 327         echo 'shopt -s expand_aliases &>/dev/null';
 328     }
 329
 330     _get_ignored_VARS() {
 331         perl -e '
 332             for(@ARGV){
 333                 $next_is_env and push @envvar, split/,/, $_;
 334                 $next_is_env=/^--env$/;
 335             }
 336             if(grep { /^_$/ } @envvar) {
 337                 if(not open(IN, "<", "$ENV{HOME}/.parallel/ignored_vars")) {
 338                     print STDERR "parallel: Error: ",
 339                     "Run \"parallel --record-env\" in a clean environment first.\n";
 340                 } else {
 341                     chomp(@ignored_vars = <IN>);
 342                 }
 343             }
 344             if($ENV{PARALLEL_IGNORED_NAMES}) {
 345                 push @ignored_vars, split/\s+/, $ENV{PARALLEL_IGNORED_NAMES};
 346                 chomp @ignored_vars;
 347             }
 348             $vars = join "|",map { quotemeta $_ } @ignored_vars;
 349             print $vars ? "($vars)" : "(,,nO,,VaRs,,)";
 350             ' -- "$@"
 351     }
 352
 353     # Get the --env variables if set
 354     # --env _ should be ignored
 355     # and convert  a b c  to (a|b|c)
 356     # If --env not set: Match everything (.*)
 357     _make_grep_REGEXP() {
 358         perl -e '
 359             for(@ARGV){
 360                 /^_$/ and $next_is_env = 0;
 361                 $next_is_env and push @envvar, split/,/, $_;
 362                 $next_is_env = /^--env$/;
 363             }
 364             $vars = join "|",map { quotemeta $_ } @envvar;
 365             print $vars ? "($vars)" : "(.*)";
 366             ' -- "$@"
 367     }
 368     _which_PAR() {
 369         # type returns:
 370         #   ll is an alias for ls -l (in ash)
 371         #   bash is a tracked alias for /bin/bash
 372         #   true is a shell builtin (in bash)
 373         #   myfunc is a function (in bash)
 374         #   myfunc is a shell function (in zsh)
 375         #   which is /usr/bin/which (in sh, bash)
 376         #   which is hashed (/usr/bin/which)
 377         #   gi is aliased to `grep -i' (in bash)
 378         #   aliased to `alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde'
 379         # Return 0 if found, 1 otherwise
 380         LANG=C type "$@" |
 381             perl -pe '$exit += (s/ is an alias for .*// ||
 382                                 s/ is aliased to .*// ||
 383                                 s/ is a function// ||
 384                                 s/ is a shell function// ||
 385                                 s/ is a shell builtin// ||
 386                                 s/.* is hashed .(\S+).$/$1/ ||
 387                                 s/.* is (a tracked alias for )?//);
 388                       END { exit not $exit }'
 389     }
 390     _warning_PAR() {
 391         echo "env_parallel: Warning: $*" >&2
 392     }
 393     _error_PAR() {
 394         echo "env_parallel: Error: $*" >&2
 395     }
 396
 397     if _which_PAR parallel >/dev/null; then
 398         true parallel found in path
 399     else
 400         # shellcheck disable=SC2016
 401         _error_PAR 'parallel must be in $PATH.'
 402         return 255
 403     fi
 404
 405     # Grep regexp for vars given by --env
 406     # shellcheck disable=SC2006
 407     _grep_REGEXP="`_make_grep_REGEXP \"$@\"`"
 408     unset _make_grep_REGEXP
 409
 410     # Deal with --env _
 411     # shellcheck disable=SC2006
 412     _ignore_UNDERSCORE="`_get_ignored_VARS \"$@\"`"
 413     unset _get_ignored_VARS
 414
 415     # --record-env
 416     if perl -e 'exit grep { /^--record-env$/ } @ARGV' -- "$@"; then
 417         true skip
 418     else
 419         (_names_of_ALIASES;
 420          _names_of_FUNCTIONS;
 421          _names_of_VARIABLES) |
 422             cat > "$HOME"/.parallel/ignored_vars
 423         return 0
 424     fi
 425
 426     # --session
 427     if perl -e 'exit grep { /^--session$/ } @ARGV' -- "$@"; then
 428         true skip
 429     else
 430         # Insert ::: between each level of session
 431         # so you can pop off the last ::: at --end-session
 432         # shellcheck disable=SC2006
 433         PARALLEL_IGNORED_NAMES="`echo \"$PARALLEL_IGNORED_NAMES\";
 434           echo :::;
 435           (_names_of_ALIASES;
 436            _names_of_FUNCTIONS;
 437            _names_of_VARIABLES) | perl -ne '
 438             BEGIN{
 439               map { $ignored_vars{$_}++ }
 440                 split/\s+/, $ENV{PARALLEL_IGNORED_NAMES};
 441             }
 442             chomp;
 443             for(split/\s+/) {
 444               if(not $ignored_vars{$_}) {
 445                 print $_,\"\\n\";
 446               }
 447             }
 448             '`"
 449         export PARALLEL_IGNORED_NAMES
 450         return 0
 451     fi
 452     if perl -e 'exit grep { /^--end.?session$/ } @ARGV' -- "$@"; then
 453         true skip
 454     else
 455         # Pop off last ::: from PARALLEL_IGNORED_NAMES
 456         # shellcheck disable=SC2006
 457         PARALLEL_IGNORED_NAMES="`perl -e '
 458           $ENV{PARALLEL_IGNORED_NAMES} =~ s/(.*):::.*?$/$1/s;
 459           print $ENV{PARALLEL_IGNORED_NAMES}
 460         '`"
 461         return 0
 462     fi
 463     # Grep alias names
 464     # shellcheck disable=SC2006
 465     _alias_NAMES="`_names_of_ALIASES | _remove_bad_NAMES | xargs echo`"
 466     _list_alias_BODIES="_bodies_of_ALIASES $_alias_NAMES"
 467     if [ "$_alias_NAMES" = "" ] ; then
 468         # no aliases selected
 469         _list_alias_BODIES="true"
 470     fi
 471     unset _alias_NAMES
 472
 473     # Grep function names
 474     # shellcheck disable=SC2006
 475     _function_NAMES="`_names_of_FUNCTIONS | _remove_bad_NAMES | xargs echo`"
 476     _list_function_BODIES="_bodies_of_FUNCTIONS $_function_NAMES"
 477     if [ "$_function_NAMES" = "" ] ; then
 478         # no functions selected
 479         _list_function_BODIES="true"
 480     fi
 481     unset _function_NAMES
 482
 483     # Grep variable names
 484     # shellcheck disable=SC2006
 485     _variable_NAMES="`_names_of_VARIABLES | _remove_bad_NAMES | xargs echo`"
 486     _list_variable_VALUES="_bodies_of_VARIABLES $_variable_NAMES"
 487     if [ "$_variable_NAMES" = "" ] ; then
 488         # no variables selected
 489         _list_variable_VALUES="true"
 490     fi
 491     unset _variable_NAMES
 492
 493     if $_eval_needed ; then
 494         # shellcheck disable=SC2006
 495         PARALLEL_ENV="`
 496         eval $_prefix_PARALLEL_ENV;
 497         eval $_list_alias_BODIES;
 498         eval $_list_function_BODIES;
 499         eval $_list_variable_VALUES;
 500         `"
 501     else
 502         # shellcheck disable=SC2006
 503         PARALLEL_ENV="`
 504         $_prefix_PARALLEL_ENV;
 505         $_list_alias_BODIES;
 506         $_list_function_BODIES;
 507         $_list_variable_VALUES;
 508         `"
 509     fi
 510     export PARALLEL_ENV
 511     # Free up some env space
 512     unset _list_alias_BODIES _list_variable_VALUES _list_function_BODIES
 513     unset _bodies_of_ALIASES _bodies_of_VARIABLES _bodies_of_FUNCTIONS
 514     unset _names_of_ALIASES _names_of_VARIABLES _names_of_FUNCTIONS
 515     unset _ignore_HARDCODED _ignore_READONLY _ignore_UNDERSCORE
 516     unset _remove_bad_NAMES _grep_REGEXP _parse_READONLY
 517     unset _prefix_PARALLEL_ENV
 518     unset _ignore_READONLY_sh _ignore_READONLY_bash
 519     unset _ignore_READONLY_ksh _ignore_READONLY_zsh
 520     unset _ignore_HARDCODED_sh _ignore_HARDCODED_bash
 521     unset _ignore_HARDCODED_ksh _ignore_HARDCODED_zsh
 522     unset _bodies_of_ALIASES_ksh _bodies_of_ALIASES_sh
 523     unset _bodies_of_ALIASES_zsh _bodies_of_FUNCTIONS_bash
 524     unset _bodies_of_FUNCTIONS_ksh _bodies_of_FUNCTIONS_sh
 525     unset _bodies_of_FUNCTIONS_zsh _bodies_of_VARIABLES_bash
 526     unset _bodies_of_VARIABLES_ksh _bodies_of_VARIABLES_sh
 527     unset _bodies_of_VARIABLES_zsh
 528     unset _names_of_ALIASES _names_of_ALIASES_bash
 529     unset _names_of_ALIASES_ksh _names_of_ALIASES_sh
 530     unset _names_of_ALIASES_zsh _names_of_FUNCTIONS
 531     unset _names_of_FUNCTIONS_bash _names_of_FUNCTIONS_ksh
 532     unset _names_of_FUNCTIONS_sh _names_of_FUNCTIONS_zsh
 533     unset _names_of_VARIABLES _names_of_VARIABLES_bash
 534     unset _names_of_VARIABLES_ksh _names_of_VARIABLES_sh
 535     unset _names_of_VARIABLES_zsh _names_of_maybe_FUNCTIONS
 536
 537     # Test if environment is too big by running 'true'
 538     # shellcheck disable=SC2006,SC2092
 539     if `_which_PAR true` >/dev/null 2>/dev/null ; then
 540         parallel "$@"
 541         _parallel_exit_CODE=$?
 542         # Clean up variables/functions
 543         unset PARALLEL_ENV
 544         unset _which_PAR _which_TRUE
 545         unset _warning_PAR _error_PAR
 546         # Unset _parallel_exit_CODE before return
 547         eval "unset _parallel_exit_CODE; return $_parallel_exit_CODE"
 548     else
 549         unset PARALLEL_ENV;
 550         _error_PAR "Your environment is too big."
 551         _error_PAR "You can try 3 different approaches:"
 552         _error_PAR "1. Run 'env_parallel --session' before you set"
 553         _error_PAR "   variables or define functions."
 554         _error_PAR "2. Use --env and only mention the names to copy."
 555         _error_PAR "3. Try running this in a clean environment once:"
 556         _error_PAR "     env_parallel --record-env"
 557         _error_PAR "   And then use '--env _'"
 558         _error_PAR "For details see: man env_parallel"
 559         return 255
 560     fi
 561 }
 562
 563 parset() {
 564     _parset_PARALLEL_PRG=parallel
 565     _parset_main "$@"
 566 }
 567
 568 env_parset() {
 569     _parset_PARALLEL_PRG=env_parallel
 570     _parset_main "$@"
 571 }
 572
 573 _parset_main() {
 574     # If $1 contains ',' or space:
 575     #   Split on , to get the destination variable names
 576     # If $1 is a single destination variable name:
 577     #   Treat it as the name of an array
 578     #
 579     #   # Create array named myvar
 580     #   parset myvar echo ::: {1..10}
 581     #   echo ${myvar[5]}
 582     #
 583     #   # Put output into $var_a $var_b $var_c
 584     #   varnames=(var_a var_b var_c)
 585     #   parset "${varnames[*]}" echo ::: {1..3}
 586     #   echo $var_c
 587     #
 588     #   # Put output into $var_a4 $var_b4 $var_c4
 589     #   parset "var_a4 var_b4 var_c4" echo ::: {1..3}
 590     #   echo $var_c4
 591
 592     _parset_NAME="$1"
 593     if [ "$_parset_NAME" = "" ] ; then
 594         echo parset: Error: No destination variable given. >&2
 595         echo parset: Error: Try: >&2
 596         echo parset: Error: ' ' parset myarray echo ::: foo bar >&2
 597         return 255
 598     fi
 599     if [ "$_parset_NAME" = "--help" ] ; then
 600         echo parset: Error: Usage: >&2
 601         echo parset: Error: ' ' parset varname GNU Parallel options and command >&2
 602         echo
 603         parallel --help
 604         return 255
 605     fi
 606     if [ "$_parset_NAME" = "--version" ] ; then
 607         # shellcheck disable=SC2006
 608         echo "parset 20240522 (GNU parallel `parallel --minversion 1`)"
 609         echo "Copyright (C) 2007-2024 Ole Tange, http://ole.tange.dk and Free Software"
 610         echo "Foundation, Inc."
 611         echo "License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>"
 612         echo "This is free software: you are free to change and redistribute it."
 613         echo "GNU parallel comes with no warranty."
 614         echo
 615         echo "Web site: https://www.gnu.org/software/parallel"
 616         echo
 617         echo "When using programs that use GNU Parallel to process data for publication"
 618         echo "please cite as described in 'parallel --citation'."
 619         echo
 620         return 255
 621     fi
 622     shift
 623
 624     # Bash: declare -A myassoc=( )
 625     # Zsh: typeset -A myassoc=( )
 626     # Ksh: typeset -A myassoc=( )
 627     # shellcheck disable=SC2039,SC2169,SC3044
 628     if (typeset -p "$_parset_NAME" 2>/dev/null; echo) |
 629             perl -ne 'exit not (/^declare[^=]+-A|^typeset[^=]+-A/)' ; then
 630         # This is an associative array
 631         # shellcheck disable=SC2006
 632         eval "`$_parset_PARALLEL_PRG -k --_parset assoc,"$_parset_NAME" "$@"`"
 633         # The eval returns the function!
 634     else
 635         # This is a normal array or a list of variable names
 636         # shellcheck disable=SC2006
 637         eval "`$_parset_PARALLEL_PRG -k --_parset var,"$_parset_NAME" "$@"`"
 638         # The eval returns the function!
 639     fi
 640 }