mdw@git.distorted.org.uk Git - runlisp/blob - runlisp.conf.5.in

   1 .\" -*-nroff-*-
   2 .\"
   3 .\" Manual for `runlisp' configuration files
   4 .\"
   5 .\" (c) 2020 Mark Wooding
   6 .\"
   7 .
   8 .\"----- Licensing notice ---------------------------------------------------
   9 .\"
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  24 .
  25 .ie t \{\
  26 .  ds o \(bu
  27 .  if \n(.g \{\
  28 .    fam P
  29 .    ev an-1
  30 .    fam P
  31 .    ev
  32 .  \}
  33 .\}
  34 .el \{\
  35 .  ds o o
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  37 .
  38 .de hP
  39 .IP
  40 \h'-\w'\fB\\$1\ \fP'u'\fB\\$1\ \fP\c
  41 ..
  42 .ds .. \&.\|.\|.
  43 .
  44 .\"--------------------------------------------------------------------------
  45 .TH runlisp.conf 5 "27 August 2020" "Mark Wooding"
  46 .SH NAME
  47 runlisp.conf \- configuration files for runlisp
  48 .
  49 .\"--------------------------------------------------------------------------
  50 .SH DESCRIPTION
  51 .
  52 .SS "Default configuration files"
  53 By default, the
  54 .B runlisp
  55 programs read configuration from the following files.
  56 (Note that if a
  57 .RB ` \-c '
  58 command-line option is given, then
  59 these default files are
  60 .I not
  61 read.)
  62 .TP
  63 .B @etcdir@/runlisp.d/*.conf
  64 If a directory named
  65 .B @etcdir@/runlisp.d
  66 exists,
  67 then all of the files within
  68 whose names end in
  69 .RB ` .conf '
  70 are read,
  71 in ascending lexicographical order by name.
  72 This directory name can be overridden by setting the
  73 .B RUNLISP_SYSCONFIG_DIR
  74 environment variable.
  75 .TP
  76 .B @etcdir@/runlisp.conf
  77 The file named
  78 .B @etcdir@/runlisp.conf
  79 is read; the file must exist.
  80 This filename can be overridden by setting the
  81 .B RUNLISP_SYSCONFIG
  82 environment variable.
  83 .TP
  84 .B ~/.runlisp.conf
  85 If there is a file named
  86 .B .runlisp.conf
  87 in the user's home directory,
  88 then it is read.
  89 The home directory is determined to be
  90 the value of the
  91 .B HOME
  92 environment variable, or, if that is not set,
  93 the home directory associated with the process's real uid
  94 in the system password database.
  95 This filename can be overridden by setting the
  96 .B RUNLISP_USERCONFIG
  97 environment variable.
  98 .TP
  99 .B ~/.config/runlisp.conf
 100 If there is a file named
 101 .B runlisp.conf
 102 in the user's XDG configuration directory,
 103 then it is read.
 104 The XDG configuration directory is determined to be the value of the
 105 .B XDG_CONFIG_HOME
 106 environment variable, or the
 107 .B .config
 108 directory in the user's home directory
 109 (as determined above).
 110 This filename can be overridden by setting the
 111 .B RUNLISP_USERCONFIG
 112 environment variable.
 113 (Note, therefore, that this variable overrides
 114 .I both
 115 of the user configuration files.)
 116 .
 117 .SS "General syntax"
 118 In summary,
 119 a configuration file is structured as a collection of assignments
 120 .I variable
 121 .B =
 122 .IR value ,
 123 gathered into named sections by header lines
 124 .BI [ section ]\fR.
 125 .PP
 126 Comments are indicated by a semicolon
 127 .RB ` ; '
 128 in the leftmost column,
 129 and extend to the end of the line;
 130 comments and lines consisting only of whiteapace are ignored
 131 and have no effect whatever.
 132 Semicolons not in the first column do
 133 .I not
 134 introduce comments,
 135 and have no special meaning.
 136 .PP
 137 A
 138 .I name
 139 is a non-empty sequence of ASCII alphanumeric characters,
 140 or the special constituent characters
 141 .RB ` \- ',
 142 .RB ` _ ',
 143 .RB ` . ',
 144 .RB ` / ',
 145 .RB ` * ',
 146 .RB ` + ',
 147 .RB ` *% ',
 148 or
 149 .RB ` @ '.
 150 For example,
 151 .RB ` foo ',
 152 .RB ` 12345 ',
 153 .RB ` \-2.718 ',
 154 .RB ` 113/355 ',
 155 .RB ` image-dir ',
 156 .RB ` @%IMAGEDIR ',
 157 and
 158 .RB ` *organa-solo* '
 159 are all names, but
 160 .RB ` foo:bar '
 161 .RB ` happy? '
 162 and
 163 .RB ` $3.95 '
 164 are not.
 165 Names beginning with
 166 .RB ` @ '
 167 are reserved for use by the
 168 .B runlisp
 169 programs;
 170 names beginning with
 171 .RB ` % '
 172 or
 173 .RB ` @% '
 174 are by convention private.
 175 .PP
 176 A
 177 .I section header
 178 is a line of the form
 179 .IP
 180 .BI [ section ]
 181 .PP
 182 where
 183 .I section
 184 is a name, as defined above.
 185 There may be whitespace before and after the
 186 .I name
 187 or after the
 188 .RB  ` ] '.
 189 Section headers need not have distinct names.
 190 Subsequent assignments are applied to the section called
 191 .IR name ,
 192 up until the next section header, or the end of the file.
 193 Assignments prior to the first section header in a file
 194 are applied to the
 195 .B @CONFIG
 196 section.
 197 .PP
 198 An
 199 .I assignment
 200 begins with a line of the form
 201 .IP
 202 .I variable
 203 .B =
 204 .I rest
 205 .PP
 206 where
 207 .I variable
 208 is a name, as defined above,
 209 and it includes all subsequent
 210 (non-empty, non-comment)
 211 lines up to, but not including,
 212 the next line which does
 213 .I not
 214 begin with whitespace or a semicolon,
 215 or the end of the input file.
 216 There may be space before or after the
 217 .RB ` = '.
 218 The
 219 .I value
 220 assigned consists of the text of the initial line following the
 221 .RB ` = '
 222 character
 223 (shown as
 224 .I rest
 225 above),
 226 together with the contents of the subsequent lines;
 227 initial and trailing whitespace is removed from each piece,
 228 and the (nonempty) pieces are joined,
 229 separated by single spaces.
 230 We say that an assignment
 231 assigns a value to the variable
 232 in some section \(en
 233 namely, the section in which the assignment is applied.
 234 .PP
 235 For example,
 236 consider the following file.
 237 .IP
 238 .ft B
 239 .nf
 240 long =
 241         one
 242
 243         two
 244 ; this line is a comment
 245         ; not a comment
 246         three
 247
 248 short = just a quick note
 249 .fi
 250 .ft P
 251 .PP
 252 Then
 253 .B long
 254 is assigned the value
 255 .RB ` "one two ; not a comment three" ',
 256 and
 257 .B short is assigned
 258 .RB ` "just a quick note" '.
 259 .PP
 260 The assignments applied to a section
 261 need not have distinct variable names.
 262 Only the last assignment to a particular variable name in a section is
 263 .IR effective ;
 264 the earlier assignments are simply ignored.
 265 If an effective assignment assigns a value to a variable in a section,
 266 we say that the variable is
 267 .I set
 268 to that value in the section.
 269 .
 270 .SS "Lookup and inheritance"
 271 A section may have zero or more
 272 .I parent
 273 sections.
 274 .PP
 275 The
 276 .B @BUILTIN
 277 and
 278 .B @ENV
 279 sections have no parents.
 280 The
 281 .B @CONFIG
 282 section has one parent, namely
 283 .BR @BUILTIN .
 284 .PP
 285 If the variable
 286 .B @parents
 287 is set in a section other than one of those named above,
 288 then it must consist of a space- or comma-separated list
 289 of names,
 290 which name the section's parents.
 291 Currently, the parents need not be distinct,
 292 though duplicates have no effect other than slowing down lookup.
 293 The order in which parents are listed is not significant.
 294 If
 295 .B @parents
 296 is not set in a section other than one of those named above,
 297 then by default it has one parent, namely
 298 .BR @COMMON .
 299 .PP
 300 It is currently possible to build a cyclic structure of parent links.
 301 This is not recommended.
 302 If lookup (explained below) detects a cycle
 303 then it will report a fatal error,
 304 but cycles may exist without being detected.
 305 .PP
 306 A variable is
 307 .I "looked up"
 308 in a section as follows.
 309 .hP 1.
 310 If there is an effective assignment
 311 of a value to that variable in the section
 312 then lookup finds that assignment.
 313 .hP 2.
 314 If the section has no parents,
 315 then lookup fails.
 316 .hP 3.
 317 Otherwise, the variable is looked up in each of the section's parents.
 318 If none of these lookups succeeds, then the lookup fails.
 319 If all of the successful lookups found the
 320 .I "same assignment"
 321 (not just the same value!)
 322 then lookup finds that assignment.
 323 Otherwise, the lookup reports an error.
 324 .
 325 .SS "Expansion and word-splitting"
 326 A value can be
 327 .I expanded
 328 relative to some home section,
 329 and optionally split into words.
 330 .PP
 331 Not all values are
 332 .IR expandable .
 333 Values set by assignments in a configuration file are always expandable.
 334 Values set on the command line \(en in
 335 .B \-o
 336 options \(en are not expandable.
 337 Values in the
 338 .B @ENV
 339 section from environment variables (see below) are not expandable.
 340 Some values set in the
 341 .B @BUILTIN
 342 section are expandable and some are not.
 343 Applying expansion to a value that is not expandable
 344 simply results in that same value, unchanged.
 345 .PP
 346 Applying expansion to an expandable value
 347 produces a result string as follows.
 348 The value is scanned from start to end.
 349 .hP \*o
 350 A backslash
 351 .RB ` \e '
 352 is discarded, but the immediately following character
 353 is copied to the output without further inspection.
 354 .hP \*o
 355 A
 356 .I variable substitution
 357 takes the form
 358 .BR ${ [ \c
 359 .IB sect : \c
 360 .RI ] var \c
 361 .RB [ | \c
 362 .IR filter ]\*(.. \c
 363 .RB [ ? \c
 364 .IR alt ] \c
 365 .BR } .
 366 A variable named
 367 .I var
 368 is looked up in the section named
 369 .IR sect ,
 370 or, if omitted, in the home section.
 371 If the lookup succeeds,
 372 then the value is expanded,
 373 processed by the
 374 .IR filter s
 375 (explained below),
 376 and appended to the output.
 377 If the lookup failed,
 378 and
 379 .BI ? alt
 380 is present,
 381 then
 382 .I alt
 383 is expanded and appended to the output.
 384 Otherwise,
 385 if the lookup fails and there is no
 386 .I alt
 387 text, then an error is reported.
 388 .IP
 389 A filter
 390 .B u
 391 causes the expanded value to be converted to uppercase;
 392 similarly,
 393 .B l
 394 causes the expanded value to be converted to lowercase.
 395 A filter
 396 .B q
 397 causes a backslash to be inserted before each
 398 backslash or double-quote character in the expanded value,
 399 so that this can be used as part of a quoted Common Lisp string.
 400 .hP \*o
 401 A
 402 .I conditional
 403 takes the form
 404 .BR $? [ \c
 405 .IB sect : \c
 406 .RI ] var \c
 407 .BI { conseq \c
 408 .RB [ | \c
 409 .IR alt ] \c
 410 .BR } .
 411 A variable named
 412 .I var
 413 is looked up in the section named
 414 .IR sect ,
 415 or, if omitted, in the home section.
 416 If the lookup succeeds, then
 417 .I conseq
 418 is expanded and appended to the output;
 419 otherwise, if
 420 .I alt
 421 is present, then it is expanded and appended to the output;
 422 otherwise, nothing happens.
 423 .hP \*o
 424 A dollar sign which doesn't introduce one of the forms above
 425 is invalid, and a fatal error is reported.
 426 .hP \*o
 427 Any other characters are simply appended to the output.
 428 .PP
 429 Word-splitting is similar but more complex.
 430 The result is not a string, but a sequence of strings.
 431 At any given point in this procedure,
 432 there may be a partially constructed word,
 433 or there might not.
 434 .hP \*o
 435 Outside of quotes (see below),
 436 whitespace serves to separate words.
 437 When a whitespace character is encountered,
 438 if there is a word under construction,
 439 then it is finished and added to the output list;
 440 otherwise it is simply ignored.
 441 .hP \*o
 442 If a backslash is encountered,
 443 then a word is started if there is none currently under construction,
 444 and the character following the backslash is added to the current word.
 445 .hP \*o
 446 If a single-quote character
 447 .RB ` ' '
 448 is encountered,
 449 then a word is started if there is none currently under construction,
 450 and
 451 .I all
 452 characters up to the next single quote
 453 are added to the current word.
 454 This includes double quotes, dollar signs, and backslashes.
 455 (Neither of the two single quotes is appended to the current word.)
 456 .hP \*o
 457 If a double-quote character
 458 .RB ` """" '
 459 is encountered,
 460 then a word is started if there is none currently under construction.
 461 Until the next double quote is encountered,
 462 whitespace and single quotes treated literally,
 463 and simply added to the current word;
 464 backslashes can be used to escape characters,
 465 such as double quotes,
 466 as usual.
 467 .hP \*o
 468 If a
 469 .BR $ -expansion
 470 \(en a variable substitution or conditional (as described above) \(en
 471 is encountered
 472 and there is a current word under construction,
 473 then the result of the
 474 .BR $ -expansion
 475 is appended to the current word.
 476 If there is no current word,
 477 then the variable value, or consequent or alternative text,
 478 is subjected to word splitting in addition to expansion,
 479 and the resulting words appended to the output sequence.
 480 .hP \*o
 481 If any other character is encountered,
 482 then a word is started if there is none currently under construction,
 483 and the character is appended to the current word.
 484 .PP
 485 One case which deserves attention:
 486 if a
 487 .BR $ -expansion
 488 is encountered outside of a word,
 489 so that the result is subject to word splitting,
 490 then an error is reported if a new word is started
 491 without there being whitespace between the closing brace of the
 492 .B $ -expansion
 493 and the character which started the new word.
 494 For example,
 495 .IP
 496 .B "bad = one ${x}two"
 497 .PP
 498 would be invalid in a word-splitting context.
 499 .
 500 .SS "Other special variables"
 501 In every section, the section's name
 502 is automatically assigned to the variable
 503 .BR @name .
 504 This variable
 505 .I can
 506 be overridden by an explicit assignment,
 507 but this is not recommended.
 508 .
 509 .SS "Predefined variables in @BUILTIN"
 510 The
 511 .B @BULITIN
 512 Section has no parents.
 513 You should not override its settings in configuration files.
 514 it holds a number of variables set by the
 515 .B runlisp
 516 programs.
 517 .
 518 .TP
 519 .B @data-dir
 520 The directory in which
 521 .BR runlisp 's
 522 auxiliary data files and scripts are located.
 523 This is determined by the
 524 .B RUNLISP_DATADIR
 525 environment variable,
 526 the
 527 .B data-dir
 528 variable in the
 529 .B @CONFIG
 530 section,
 531 or a value determined at compile time.
 532 .
 533 .TP
 534 .B @ecl-opt
 535 The preferred option prefix for ECL, either
 536 .RB ` \- '
 537 or
 538 .RB ` \-\- '.
 539 (For some reason,
 540 the ECL developers are changing
 541 the way ECL recognizes command-line options,
 542 because they think that the minor aesthetic improvement
 543 is worth breaking everyone's scripts.)
 544 This is determined by the
 545 .B ecl-opt
 546 variable in the
 547 .B @CONFIG
 548 section,
 549 or a value determined at compile time.
 550 .
 551 .TP
 552 .B @hash
 553 Set by
 554 .BR dump-runlisp-image (1)
 555 to the hash
 556 (a string of hexadecimal digits)
 557 identifying the versions of the Lisp code included
 558 \(en or to be included \(en
 559 in a custom image.
 560 This is constructed by hashing the result of evaluating the
 561 .B lisp-version
 562 expression in the system definition.
 563 .
 564 .TP
 565 .B @image-dir
 566 The directory in which
 567 .B runlisp
 568 looks for, and
 569 .B dump-runlisp-image
 570 stores, custom Lisp images.
 571 This is determined by the
 572 .B RUNLISP_IMAGEDIR
 573 environment variable,
 574 the
 575 .B image-dir
 576 variable in the
 577 .B @CONFIG
 578 section,
 579 or a value determined at compile time.
 580 .
 581 .TP
 582 .B @image-link
 583 The well-known name of the image;
 584 actually a symbolic link to the `real' image file,
 585 whose name includes a hash
 586 which identifies the versions of the Lisp code included in the image.
 587 .
 588 .TP
 589 .B @image-new
 590 Set by
 591 .BR dump-runlisp-image (1)
 592 to the filename that a
 593 .B dump-image
 594 command should create.
 595 .RB ( dump-runlisp-image
 596 will rename the image into place itself,
 597 if the command completes successfully.)
 598 .
 599 .TP
 600 .B @image-newlink
 601 Set by
 602 .BR dump-runlisp-image (1)
 603 to the name to use for the updated symbolic link to the image file.
 604 This is used internally,
 605 and is not expected to be useful in Lisp system definitions.
 606 .
 607 .TP
 608 .B @image-out
 609 Set by
 610 .BR dump-runlisp-image (1)
 611 to the filename of the intended output image.
 612 (Don't use this in
 613 .B dump-image
 614 commands: use
 615 .B @image-new
 616 instread.)
 617 .
 618 .TP
 619 .B @script
 620 Set by
 621 .BR runlisp (1)
 622 to the name of the script being invoked.
 623 .
 624 .TP
 625 .B @tmp-dir
 626 Set by
 627 .BR dump-runlisp-image (1)
 628 to be the name of a directory in which a
 629 .B dump-image
 630 command can put temporary files.
 631 .
 632 .SS "Environment variables in @ENV"
 633 The
 634 .B @ENV
 635 section is special,
 636 and is used to hold a copy of the system environment.
 637 At startup,
 638 it contains an assignment for every environment variable.
 639 The
 640 .B @ENV
 641 section has no parents.
 642 The values are not expandable.
 643 It is possible to override
 644 .B @ENV
 645 settings in configuration files
 646 or on the command line,
 647 but this is not recommended.
 648 .
 649 .SS "The @COMMON section"
 650 The
 651 .B @COMMON section
 652 is the default parent for nearly all other configuration sections
 653 (the exceptions being
 654 .B @BUILTIN
 655 and
 656 .BR @ENV ,
 657 which have no parents, and
 658 .B @COMMON
 659 itself, whose parent is
 660 .BR @BUILTIN ).
 661 It is used in the provided configuration
 662 to hold various common snippets of Lisp code and other settings,
 663 but the
 664 .B runlisp
 665 programs themselves make no direct use of it.
 666 .
 667 .SS "Overall configuration in @CONFIG"
 668 Variable settings in
 669 .B @CONFIG
 670 are consulted for various administrative reasons.
 671 .PP
 672 Because of the open-ended nature of this configuration mechanism,
 673 users can easily invent new configuration variables
 674 for any purpose they can imagine.
 675 The following variables are used by the
 676 .B runlisp
 677 programs directly, or its default configuration.
 678 All values are expanded before use;
 679 the
 680 .B @CONFIG
 681 section's parent is
 682 .BR @COMMON ,
 683 as usual.
 684 .
 685 .TP
 686 .B data-dir
 687 The directory in which
 688 .BR runlisp 's
 689 auxiliary data files and scripts are located.
 690 There is a hardcoded default
 691 determined at compile-time,
 692 which is probably correct.
 693 Overridden by the
 694 .B RUNLISP_DATADIR
 695 environment variable.
 696 Don't refer to this setting directly:
 697 expand
 698 .B @data-dir
 699 from the
 700 .B @BUILTIN
 701 section instead.
 702 .
 703 .TP
 704 .B dump
 705 A comma-separated list of Lisp implementation names
 706 which should have custom images dumped by
 707 .BR "dump-runlisp-image \-a" .
 708 The order is not especially significant.
 709 The default is all of the configured implementations
 710 which define a
 711 .B dump-image
 712 variable
 713 and whose command can be found.
 714 .
 715 .TP
 716 .B ecl-opt
 717 The preferred option prefix for ECL, either
 718 .RB ` \- '
 719 or
 720 .RB ` \-\- '.
 721 There is a hardcoded default
 722 determined at compile-time,
 723 which was correct for the system on which
 724 .B runlisp
 725 was built.
 726 Don't refer to this setting directly:
 727 expand
 728 .B @ecl-opt
 729 from the
 730 .B @BUILTIN
 731 section instead.
 732 .
 733 .TP
 734 .B @image-dir
 735 The directory in which
 736 .B runlisp
 737 looks for, and
 738 .B dump-runlisp-image
 739 stores, custom Lisp images.
 740 Overridden by the
 741 .B RUNLISP_IMAGEDIR
 742 environment variable.
 743 Don't refer to this setting directly:
 744 expand
 745 .B @image-dir
 746 from the
 747 .B @BUILTIN
 748 section instead.
 749 .
 750 .TP
 751 .B prefer
 752 A comma-separated list of names of
 753 .I preferred
 754 Lisp implementations,
 755 Overridden by the
 756 .B RUNLISP_PREFER
 757 environment variable.
 758 .
 759 .SS "Lisp implementation definitions"
 760 A Lisp implementation is described to
 761 .B runlisp
 762 by a configuration section.
 763 The section's name is used to refer to the implementation,
 764 e.g., in
 765 .BR runlisp 's
 766 .B \-L
 767 option,
 768 or in the
 769 .B dump
 770 and
 771 .B prefer
 772 lists described above.
 773 .PP
 774 The following variable settings are used directly;
 775 of course, a Lisp implementation definition may contain other settings
 776 for internal purposes.
 777 .
 778 .TP
 779 .B command
 780 The name of the program used to invoke the Lisp implementation.
 781 .BR dump-runlisp-image
 782 looks to see whether this program is installed when invoked with the
 783 .B \-i
 784 option:
 785 it will fail if there is no
 786 .B command
 787 setting.
 788 It is also commonly
 789 (but not universally)
 790 used in the
 791 .B run-script
 792 and
 793 .B dump-image
 794 variables.
 795 It's conventional to set this to
 796 .B ${@ENV:FOO?foo}
 797 so that the command name can be overridden from the environment.
 798 .
 799 .TP
 800 .B dump-image
 801 The complete command to use to dump a custom image
 802 for this Lisp implementation.
 803 The value is subjected to expansion and word-splitting before use.
 804 It should write the newly created image to the file named by the
 805 .B @image-new
 806 setting in the
 807 .B @BUILTIN
 808 section.
 809 .
 810 .TP
 811 .B image-file
 812 The basename of the custom image file
 813 (i.e., not containing any
 814 .BR ` / '
 815 characters)
 816 to use when invoking this Lisp implementation.
 817 .BR runlisp (1)
 818 and
 819 .BR dump-runlisp-image (1)
 820 use the presence of this setting to decide
 821 whether the implementation supports custom images.
 822 .
 823 .TP
 824 .B image-path
 825 The complete (but not necessarily absolute) pathname
 826 of the custom image file for this Lisp implementation.
 827 It is the (expanded) value of this variable
 828 which is used by
 829 .BR runlisp (1)
 830 when it checks whether a custom image exists.
 831 It's set to
 832 .B ${@image-dir}/${image-file}
 833 in the standard configuration file's
 834 .B @COMMON
 835 section,
 836 and there is probably no need to override it;
 837 .B @image-dir
 838 is set in the
 839 .B @BUILTIN
 840 section
 841 .RB ( @image-dir
 842 is set in the
 843 .N @BUILTIN
 844 section \(en see above \(en and
 845 .B image-file
 846 must be set in this section
 847 (or one of its ancestors)
 848 before
 849 .BR runlisp (1)
 850 would not attempt to check for an image file.
 851 .
 852 .TP
 853 .B run-script
 854 The complete command to use
 855 to get this Lisp implementation to execute a script.
 856 The value is subjected to expansion and word-splitting before use.
 857 The script name is available as
 858 .B @script
 859 in the
 860 .B @BUILTIN
 861 section \(en see above.
 862 If a custom image is available, then
 863 .B @image
 864 is defined
 865 (to the value
 866 .BR t )
 867 .I "in this section"
 868 (not in
 869 .BR @BUILTIN );
 870 the full path to the image file to use is given by
 871 .B ${image-path}
 872 \(en see above.
 873 .
 874 .\"--------------------------------------------------------------------------
 875 .
 876 .SH SEE ALSO
 877 .BR dump-runlisp-image (1),
 878 .BR query-runlisp-config (1),
 879 .BR runlisp (1).
 880 .
 881 .SH AUTHOR
 882 Mark Wooding, <mdw@distorted.org.uk>
 883 .
 884 .\"----- That's all, folks --------------------------------------------------