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3 .\" Copyright (c) 1990, 1993
4 .\" The Regents of the University of California. All rights reserved.
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9 .\" 1. Redistributions of source code must retain the above copyright
10 .\" notice, this list of conditions and the following disclaimer.
11 .\" 2. Redistributions in binary form must reproduce the above copyright
12 .\" notice, this list of conditions and the following disclaimer in the
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16 .\" without specific prior written permission.
18 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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30 .\" from: @(#)make.1 8.4 (Berkeley) 3/19/94
37 .Nd maintain program dependencies
56 is a program designed to simplify the maintenance of other programs.
57 Its input is a list of specifications as to the files upon which programs
58 and other files depend.
61 makefile option is given,
67 in order to find the specifications.
70 exists, it is read (see
73 This manual page is intended as a reference document only.
74 For a more thorough description of
76 and makefiles, please refer to
77 .%T "PMake \- A Tutorial" .
80 will prepend the contents of the
82 environment variable to the command line arguments before parsing them.
84 The options are as follows:
87 Try to be backwards compatible by executing a single shell per command and
88 by executing the commands to make the sources of a dependency line in sequence.
92 before reading the makefiles or doing anything else.
95 options are specified, each is interpreted relative to the previous one:
96 .Fl C Pa / Fl C Pa etc
102 to be 1, in the global context.
104 Turn on debugging, and specify which portions of
106 are to print debugging information.
107 Unless the flags are preceded by
109 they are added to the
111 environment variable and will be processed by any child make processes.
112 By default, debugging information is printed to standard error,
113 but this can be changed using the
116 The debugging output is always unbuffered; in addition, if debugging
117 is enabled but debugging output is not directed to standard output,
118 then the standard output is line buffered.
120 is one or more of the following:
123 Print all possible debugging information;
124 equivalent to specifying all of the debugging flags.
126 Print debugging information about archive searching and caching.
128 Print debugging information about current working directory.
130 Print debugging information about conditional evaluation.
132 Print debugging information about directory searching and caching.
134 Print debugging information about failed commands and targets.
135 .It Ar F Ns Oo Sy \&+ Oc Ns Ar filename
136 Specify where debugging output is written.
137 This must be the last flag, because it consumes the remainder of
139 If the character immediately after the
143 then the file will be opened in append mode;
144 otherwise the file will be overwritten.
149 then debugging output will be written to the
150 standard output or standard error output file descriptors respectively
153 option has no effect).
154 Otherwise, the output will be written to the named file.
155 If the file name ends
159 is replaced by the pid.
161 Print debugging information about loop evaluation.
163 Print the input graph before making anything.
165 Print the input graph after making everything, or before exiting
168 Print the input graph before exiting on error.
170 Print debugging information about running multiple shells.
172 Print commands in Makefiles regardless of whether or not they are prefixed by
174 or other "quiet" flags.
175 Also known as "loud" behavior.
177 Print debugging information about "meta" mode decisions about targets.
179 Print debugging information about making targets, including modification
182 Don't delete the temporary command scripts created when running commands.
183 These temporary scripts are created in the directory
186 environment variable, or in
190 is unset or set to the empty string.
191 The temporary scripts are created by
193 and have names of the form
196 This can create many files in
202 Print debugging information about makefile parsing.
204 Print debugging information about suffix-transformation rules.
206 Print debugging information about target list maintenance.
210 option to print raw values of variables, overriding the default behavior
212 .Va .MAKE.EXPAND_VARIABLES .
214 Print debugging information about variable assignment.
216 Run shell commands with
218 so the actual commands are printed as they are executed.
221 Specify that environment variables override macro assignments within
224 Specify a makefile to read instead of the default
230 standard input is read.
231 Multiple makefiles may be specified, and are read in the order specified.
232 .It Fl I Ar directory
233 Specify a directory in which to search for makefiles and included makefiles.
234 The system makefile directory (or directories, see the
236 option) is automatically included as part of this list.
238 Ignore non-zero exit of shell commands in the makefile.
239 Equivalent to specifying
241 before each command line in the makefile.
245 be specified by the user.
249 option is in use in a recursive build, this option is passed by a make
250 to child makes to allow all the make processes in the build to
251 cooperate to avoid overloading the system.
253 Specify the maximum number of jobs that
255 may have running at any one time.
256 The value is saved in
258 Turns compatibility mode off, unless the
260 flag is also specified.
261 When compatibility mode is off, all commands associated with a
262 target are executed in a single shell invocation as opposed to the
263 traditional one shell invocation per line.
264 This can break traditional scripts which change directories on each
265 command invocation and then expect to start with a fresh environment
267 It is more efficient to correct the scripts rather than turn backwards
270 Continue processing after errors are encountered, but only on those targets
271 that do not depend on the target whose creation caused the error.
272 .It Fl m Ar directory
273 Specify a directory in which to search for sys.mk and makefiles included
275 .Li \&< Ns Ar file Ns Li \&> Ns -style
279 option can be used multiple times to form a search path.
280 This path will override the default system include path: /usr/share/mk.
281 Furthermore the system include path will be appended to the search path used
283 .Li \*q Ns Ar file Ns Li \*q Ns -style
284 include statements (see the
288 If a file or directory name in the
292 environment variable) starts with the string
296 will search for the specified file or directory named in the remaining part
297 of the argument string.
298 The search starts with the current directory of
299 the Makefile and then works upward towards the root of the file system.
300 If the search is successful, then the resulting directory replaces the
305 If used, this feature allows
307 to easily search in the current source tree for customized sys.mk files
312 Display the commands that would have been executed, but do not
313 actually execute them unless the target depends on the .MAKE special
316 Display the commands which would have been executed, but do not
317 actually execute any of them; useful for debugging top-level makefiles
318 without descending into subdirectories.
320 Do not execute any commands, but exit 0 if the specified targets are
321 up-to-date and 1, otherwise.
323 Do not use the built-in rules specified in the system makefile.
325 Do not echo any commands as they are executed.
326 Equivalent to specifying
328 before each command line in the makefile.
329 .It Fl T Ar tracefile
333 append a trace record to
335 for each job started and completed.
337 Rather than re-building a target as specified in the makefile, create it
338 or update its modification time to make it appear up-to-date.
342 Do not build any targets.
343 Multiple instances of this option may be specified;
344 the variables will be printed one per line,
345 with a blank line for each null or undefined variable.
346 The value printed is extracted from the global context after all
347 makefiles have been read.
348 By default, the raw variable contents (which may
349 include additional unexpanded variable references) are shown.
354 then the value will be recursively expanded to its complete resultant
355 text before printing.
356 The expanded value will also be printed if
357 .Va .MAKE.EXPAND_VARIABLES
361 option has not been used to override it.
362 Note that loop-local and target-local variables, as well as values
363 taken temporarily by global variables during makefile processing, are
364 not accessible via this option.
367 debug mode can be used to see these at the cost of generating
368 substantial extraneous output.
372 but the variable is always expanded to its complete value.
374 Treat any warnings during makefile parsing as errors.
376 Print entering and leaving directory messages, pre and post processing.
378 Don't export variables passed on the command line to the environment
380 Variables passed on the command line are still exported
383 environment variable.
384 This option may be useful on systems which have a small limit on the
385 size of command arguments.
386 .It Ar variable=value
387 Set the value of the variable
391 Normally, all values passed on the command line are also exported to
392 sub-makes in the environment.
395 flag disables this behavior.
396 Variable assignments should follow options for POSIX compatibility
397 but no ordering is enforced.
400 There are seven different types of lines in a makefile: file dependency
401 specifications, shell commands, variable assignments, include statements,
402 conditional directives, for loops, and comments.
404 In general, lines may be continued from one line to the next by ending
405 them with a backslash
407 The trailing newline character and initial whitespace on the following
408 line are compressed into a single space.
409 .Sh FILE DEPENDENCY SPECIFICATIONS
410 Dependency lines consist of one or more targets, an operator, and zero
412 This creates a relationship where the targets
415 and are usually created from them.
416 The exact relationship between the target and the source is determined
417 by the operator that separates them.
418 The three operators are as follows:
421 A target is considered out-of-date if its modification time is less than
422 those of any of its sources.
423 Sources for a target accumulate over dependency lines when this operator
425 The target is removed if
429 Targets are always re-created, but not until all sources have been
430 examined and re-created as necessary.
431 Sources for a target accumulate over dependency lines when this operator
433 The target is removed if
437 If no sources are specified, the target is always re-created.
438 Otherwise, a target is considered out-of-date if any of its sources has
439 been modified more recently than the target.
440 Sources for a target do not accumulate over dependency lines when this
442 The target will not be removed if
447 Targets and sources may contain the shell wildcard values
458 may only be used as part of the final
459 component of the target or source, and must be used to describe existing
463 need not necessarily be used to describe existing files.
464 Expansion is in directory order, not alphabetically as done in the shell.
466 Each target may have associated with it one or more lines of shell
468 used to create the target.
469 Each of the lines in this script
471 be preceded by a tab.
472 (For historical reasons, spaces are not accepted.)
473 While targets can appear in many dependency lines if desired, by
474 default only one of these rules may be followed by a creation
478 operator is used, however, all rules may include scripts and the
479 scripts are executed in the order found.
481 Each line is treated as a separate shell command, unless the end of
482 line is escaped with a backslash
484 in which case that line and the next are combined.
485 .\" The escaped newline is retained and passed to the shell, which
486 .\" normally ignores it.
487 .\" However, the tab at the beginning of the following line is removed.
488 If the first characters of the command are any combination of
493 the command is treated specially.
496 causes the command not to be echoed before it is executed.
499 causes the command to be executed even when
502 This is similar to the effect of the .MAKE special source,
503 except that the effect can be limited to a single line of a script.
506 in compatibility mode
507 causes any non-zero exit status of the command line to be ignored.
511 is run in jobs mode with
513 the entire script for the target is fed to a
514 single instance of the shell.
515 In compatibility (non-jobs) mode, each command is run in a separate process.
516 If the command contains any shell meta characters
517 .Pq Ql #=|^(){};&<>*?[]:$`\e\en
518 it will be passed to the shell; otherwise
520 will attempt direct execution.
521 If a line starts with
523 and the shell has ErrCtl enabled then failure of the command line
524 will be ignored as in compatibility mode.
527 affects the entire job;
528 the script will stop at the first command line that fails,
529 but the target will not be deemed to have failed.
531 Makefiles should be written so that the mode of
533 operation does not change their behavior.
534 For example, any command which needs to use
538 without potentially changing the directory for subsequent commands
539 should be put in parentheses so it executes in a subshell.
540 To force the use of one shell, escape the line breaks so as to make
541 the whole script one command.
543 .Bd -literal -offset indent
544 avoid-chdir-side-effects:
545 @echo Building $@ in `pwd`
546 @(cd ${.CURDIR} && ${MAKE} $@)
549 ensure-one-shell-regardless-of-mode:
550 @echo Building $@ in `pwd`; \e
551 (cd ${.CURDIR} && ${MAKE} $@); \e
561 before executing any targets, each child process
562 starts with that as its current working directory.
563 .Sh VARIABLE ASSIGNMENTS
564 Variables in make are much like variables in the shell, and, by tradition,
565 consist of all upper-case letters.
566 .Ss Variable assignment modifiers
567 The five operators that can be used to assign values to variables are as
571 Assign the value to the variable.
572 Any previous value is overridden.
574 Append the value to the current value of the variable.
576 Assign the value to the variable if it is not already defined.
578 Assign with expansion, i.e. expand the value before assigning it
580 Normally, expansion is not done until the variable is referenced.
582 References to undefined variables are
585 This can cause problems when variable modifiers are used.
587 Expand the value and pass it to the shell for execution and assign
588 the result to the variable.
589 Any newlines in the result are replaced with spaces.
592 Any white-space before the assigned
594 is removed; if the value is being appended, a single space is inserted
595 between the previous contents of the variable and the appended value.
597 Variables are expanded by surrounding the variable name with either
602 and preceding it with
605 If the variable name contains only a single letter, the surrounding
606 braces or parentheses are not required.
607 This shorter form is not recommended.
609 If the variable name contains a dollar, then the name itself is expanded first.
610 This allows almost arbitrary variable names, however names containing dollar,
611 braces, parenthesis, or whitespace are really best avoided!
613 If the result of expanding a variable contains a dollar sign
615 the string is expanded again.
617 Variable substitution occurs at three distinct times, depending on where
618 the variable is being used.
621 Variables in dependency lines are expanded as the line is read.
623 Variables in shell commands are expanded when the shell command is
627 loop index variables are expanded on each loop iteration.
628 Note that other variables are not expanded inside loops so
629 the following example code:
630 .Bd -literal -offset indent
644 .Bd -literal -offset indent
649 Because while ${a} contains
651 after the loop is executed, ${b}
656 since after the loop completes ${j} contains
660 The four different classes of variables (in order of increasing precedence)
663 .It Environment variables
664 Variables defined as part of
668 Variables defined in the makefile or in included makefiles.
669 .It Command line variables
670 Variables defined as part of the command line.
672 Variables that are defined specific to a certain target.
675 Local variables are all built in and their values vary magically from
677 It is not currently possible to define new local variables.
678 The seven local variables are as follows:
679 .Bl -tag -width ".ARCHIVE" -offset indent
681 The list of all sources for this target; also known as
684 The name of the archive file; also known as
687 In suffix-transformation rules, the name/path of the source from which the
688 target is to be transformed (the
690 source); also known as
692 It is not defined in explicit rules.
694 The name of the archive member; also known as
697 The list of sources for this target that were deemed out-of-date; also
701 The file prefix of the target, containing only the file portion, no suffix
702 or preceding directory components; also known as
704 The suffix must be one of the known suffixes declared with
706 or it will not be recognized.
708 The name of the target; also known as
710 For compatibility with other makes this is an alias for
712 in archive member rules.
724 are permitted for backward
725 compatibility with historical makefiles and legacy POSIX make and are
728 Variants of these variables with the punctuation followed immediately by
734 are legacy forms equivalent to using the
739 These forms are accepted for compatibility with
741 makefiles and POSIX but are not recommended.
743 Four of the local variables may be used in sources on dependency lines
744 because they expand to the proper value for each target on the line.
751 .Ss Additional built-in variables
754 sets or knows about the following variables:
755 .Bl -tag -width .MAKEOVERRIDES
761 expands to a single dollar
764 The list of all targets encountered in the Makefile.
766 Makefile parsing, lists only those targets encountered thus far.
768 A path to the directory where
771 Refer to the description of
774 .It Va .INCLUDEDFROMDIR
775 The directory of the file this Makefile was included from.
776 .It Va .INCLUDEDFROMFILE
777 The filename of the file this Makefile was included from.
788 The preferred variable to use is the environment variable
790 because it is more compatible with other versions of
792 and cannot be confused with the special target with the same name.
793 .It Va .MAKE.DEPENDFILE
794 Names the makefile (default
796 from which generated dependencies are read.
797 .It Va .MAKE.EXPAND_VARIABLES
798 A boolean that controls the default behavior of the
801 If true, variable values printed with
803 are fully expanded; if false, the raw variable contents (which may
804 include additional unexpanded variable references) are shown.
805 .It Va .MAKE.EXPORTED
806 The list of variables exported by
812 .It Va .MAKE.JOB.PREFIX
817 then output for each target is prefixed with a token
819 the first part of which can be controlled via
820 .Va .MAKE.JOB.PREFIX .
823 is empty, no token is printed.
826 .Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
827 would produce tokens like
828 .Ql ---make[1234] target ---
829 making it easier to track the degree of parallelism being achieved.
831 The environment variable
833 may contain anything that
837 Anything specified on
839 command line is appended to the
841 variable which is then
842 entered into the environment for all programs which
846 The recursion depth of
848 The initial instance of
850 will be 0, and an incremented value is put into the environment
851 to be seen by the next generation.
852 This allows tests like:
853 .Li .if ${.MAKE.LEVEL} == 0
854 to protect things which should only be evaluated in the initial instance of
856 .It Va .MAKE.MAKEFILE_PREFERENCE
857 The ordered list of makefile names
864 .It Va .MAKE.MAKEFILES
865 The list of makefiles read by
867 which is useful for tracking dependencies.
868 Each makefile is recorded only once, regardless of the number of times read.
870 Processed after reading all makefiles.
871 Can affect the mode that
874 It can contain a number of keywords:
875 .Bl -hang -width missing-filemon=bf.
885 into "meta" mode, where meta files are created for each target
886 to capture the command run, the output generated and if
888 is available, the system calls which are of interest to
890 The captured output can be very useful when diagnosing errors.
891 .It Pa curdirOk= Ar bf
894 will not create .meta files in
896 This can be overridden by setting
898 to a value which represents True.
899 .It Pa missing-meta= Ar bf
902 is True, then a missing .meta file makes the target out-of-date.
903 .It Pa missing-filemon= Ar bf
906 is True, then missing filemon data makes the target out-of-date.
911 For debugging, it can be useful to include the environment
914 If in "meta" mode, print a clue about the target being built.
915 This is useful if the build is otherwise running silently.
916 The message printed the value of:
917 .Va .MAKE.META.PREFIX .
919 Some makefiles have commands which are simply not stable.
920 This keyword causes them to be ignored for
921 determining whether a target is out of date in "meta" mode.
927 is True, when a .meta file is created, mark the target
930 .It Va .MAKE.META.BAILIWICK
931 In "meta" mode, provides a list of prefixes which
932 match the directories controlled by
934 If a file that was generated outside of
936 but within said bailiwick is missing,
937 the current target is considered out-of-date.
938 .It Va .MAKE.META.CREATED
939 In "meta" mode, this variable contains a list of all the meta files
941 If not empty, it can be used to trigger processing of
942 .Va .MAKE.META.FILES .
943 .It Va .MAKE.META.FILES
944 In "meta" mode, this variable contains a list of all the meta files
945 used (updated or not).
946 This list can be used to process the meta files to extract dependency
948 .It Va .MAKE.META.IGNORE_PATHS
949 Provides a list of path prefixes that should be ignored;
950 because the contents are expected to change over time.
951 The default list includes:
952 .Ql Pa /dev /etc /proc /tmp /var/run /var/tmp
953 .It Va .MAKE.META.IGNORE_PATTERNS
954 Provides a list of patterns to match against pathnames.
955 Ignore any that match.
956 .It Va .MAKE.META.IGNORE_FILTER
957 Provides a list of variable modifiers to apply to each pathname.
958 Ignore if the expansion is an empty string.
959 .It Va .MAKE.META.PREFIX
960 Defines the message printed for each meta file updated in "meta verbose" mode.
961 The default value is:
962 .Dl Building ${.TARGET:H:tA}/${.TARGET:T}
963 .It Va .MAKEOVERRIDES
964 This variable is used to record the names of variables assigned to
965 on the command line, so that they may be exported as part of
967 This behavior can be disabled by assigning an empty value to
968 .Ql Va .MAKEOVERRIDES
970 Extra variables can be exported from a makefile
971 by appending their names to
972 .Ql Va .MAKEOVERRIDES .
974 is re-exported whenever
975 .Ql Va .MAKEOVERRIDES
977 .It Va .MAKE.PATH_FILEMON
982 support, this is set to the path of the device node.
983 This allows makefiles to test for this support.
988 The parent process-id of
990 .It Va .MAKE.SAVE_DOLLARS
991 value should be a boolean that controls whether
993 are preserved when doing
996 The default is false, for backwards compatibility.
997 Set to true for compatability with other makes.
1002 per normal evaluation rules.
1003 .It Va MAKE_PRINT_VAR_ON_ERROR
1006 stops due to an error, it sets
1007 .Ql Va .ERROR_TARGET
1008 to the name of the target that failed,
1010 to the commands of the failed target,
1011 and in "meta" mode, it also sets
1016 .Ql Va .ERROR_META_FILE
1017 to the path of the meta file (if any) describing the failed target.
1018 It then prints its name and the value of
1020 as well as the value of any variables named in
1021 .Ql Va MAKE_PRINT_VAR_ON_ERROR .
1023 This variable is simply assigned a newline character as its value.
1024 This allows expansions using the
1026 modifier to put a newline between
1027 iterations of the loop rather than a space.
1028 For example, the printing of
1029 .Ql Va MAKE_PRINT_VAR_ON_ERROR
1030 could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
1032 A path to the directory where the targets are built.
1033 Its value is determined by trying to
1035 to the following directories in order and using the first match:
1038 .Ev ${MAKEOBJDIRPREFIX}${.CURDIR}
1041 .Ql Ev MAKEOBJDIRPREFIX
1042 is set in the environment or on the command line.)
1048 is set in the environment or on the command line.)
1050 .Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE}
1052 .Ev ${.CURDIR} Ns Pa /obj
1054 .Pa /usr/obj/ Ns Ev ${.CURDIR}
1059 Variable expansion is performed on the value before it's used,
1060 so expressions such as
1061 .Dl ${.CURDIR:S,^/usr/src,/var/obj,}
1063 This is especially useful with
1067 may be modified in the makefile via the special target
1073 to the specified directory if it exists, and set
1077 to that directory before executing any targets.
1080 A path to the directory of the current
1084 The basename of the current
1089 are both set only while the
1092 If you want to retain their current values, assign them to a variable
1093 using assignment with expansion:
1096 A variable that represents the list of directories that
1098 will search for files.
1099 The search list should be updated using the target
1101 rather than the variable.
1103 Alternate path to the current directory.
1107 to the canonical path given by
1109 However, if the environment variable
1111 is set and gives a path to the current directory, then
1118 This behavior is disabled if
1119 .Ql Ev MAKEOBJDIRPREFIX
1122 contains a variable transform.
1124 is set to the value of
1126 for all programs which
1130 The list of targets explicitly specified on the command line, if any.
1134 lists of directories that
1136 will search for files.
1137 The variable is supported for compatibility with old make programs only,
1142 .Ss Variable modifiers
1143 Variable expansion may be modified to select or modify each word of the
1146 is white-space delimited sequence of characters).
1147 The general format of a variable expansion is as follows:
1149 .Dl ${variable[:modifier[:...]]}
1151 Each modifier begins with a colon,
1152 which may be escaped with a backslash
1155 A set of modifiers can be specified via a variable, as follows:
1157 .Dl modifier_variable=modifier[:...]
1158 .Dl ${variable:${modifier_variable}[:...]}
1160 In this case the first modifier in the modifier_variable does not
1161 start with a colon, since that must appear in the referencing
1163 If any of the modifiers in the modifier_variable contain a dollar sign
1165 these must be doubled to avoid early expansion.
1167 The supported modifiers are:
1170 Replaces each word in the variable with its suffix.
1172 Replaces each word in the variable with everything but the last component.
1173 .It Cm \&:M Ns Ar pattern
1174 Select only those words that match
1176 The standard shell wildcard characters
1183 The wildcard characters may be escaped with a backslash
1185 As a consequence of the way values are split into words, matched,
1186 and then joined, a construct like
1188 will normalize the inter-word spacing, removing all leading and
1189 trailing space, and converting multiple consecutive spaces
1192 .It Cm \&:N Ns Ar pattern
1193 This is identical to
1195 but selects all words which do not match
1198 Order every word in variable alphabetically.
1200 Order every word in variable in reverse alphabetical order.
1202 Randomize words in variable.
1203 The results will be different each time you are referring to the
1204 modified variable; use the assignment with expansion
1206 to prevent such behavior.
1208 .Bd -literal -offset indent
1209 LIST= uno due tre quattro
1210 RANDOM_LIST= ${LIST:Ox}
1211 STATIC_RANDOM_LIST:= ${LIST:Ox}
1214 @echo "${RANDOM_LIST}"
1215 @echo "${RANDOM_LIST}"
1216 @echo "${STATIC_RANDOM_LIST}"
1217 @echo "${STATIC_RANDOM_LIST}"
1219 may produce output similar to:
1220 .Bd -literal -offset indent
1227 Quotes every shell meta-character in the variable, so that it can be passed
1228 safely to the shell.
1230 Quotes every shell meta-character in the variable, and also doubles
1232 characters so that it can be passed
1233 safely through recursive invocations of
1235 This is equivalent to:
1236 .Sq \&:S/\e\&$/&&/g:Q .
1238 Replaces each word in the variable with everything but its suffix.
1239 .It Cm \&:range[=count]
1240 The value is an integer sequence representing the words of the original
1241 value, or the supplied
1243 .It Cm \&:gmtime[=utc]
1244 The value is a format string for
1250 value is not provided or is 0, the current time is used.
1252 Compute a 32-bit hash of the value and encode it as hex digits.
1253 .It Cm \&:localtime[=utc]
1254 The value is a format string for
1260 value is not provided or is 0, the current time is used.
1262 Attempt to convert variable to an absolute path using
1264 if that fails, the value is unchanged.
1266 Converts variable to lower-case letters.
1267 .It Cm \&:ts Ns Ar c
1268 Words in the variable are normally separated by a space on expansion.
1269 This modifier sets the separator to the character
1273 is omitted, then no separator is used.
1274 The common escapes (including octal numeric codes), work as expected.
1276 Converts variable to upper-case letters.
1278 Causes the value to be treated as a single word
1279 (possibly containing embedded white space).
1283 Causes the value to be treated as a sequence of
1284 words delimited by white space.
1288 .It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW
1290 Modify the first occurrence of
1292 in the variable's value, replacing it with
1296 is appended to the last slash of the pattern, all occurrences
1297 in each word are replaced.
1300 is appended to the last slash of the pattern, only the first word
1304 is appended to the last slash of the pattern,
1305 then the value is treated as a single word
1306 (possibly containing embedded white space).
1312 is anchored at the beginning of each word.
1315 ends with a dollar sign
1317 it is anchored at the end of each word.
1328 Any character may be used as a delimiter for the parts of the modifier
1330 The anchoring, ampersand and delimiter characters may be escaped with a
1334 Variable expansion occurs in the normal fashion inside both
1338 with the single exception that a backslash is used to prevent the expansion
1341 not a preceding dollar sign as is usual.
1343 .It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW
1347 modifier is just like the
1349 modifier except that the old and new strings, instead of being
1350 simple strings, are an extended regular expression (see
1358 Normally, the first occurrence of the pattern
1360 in each word of the value is substituted with
1364 modifier causes the substitution to apply to at most one word; the
1366 modifier causes the substitution to apply to as many instances of the
1369 as occur in the word or words it is found in; the
1371 modifier causes the value to be treated as a single word
1372 (possibly containing embedded white space).
1377 are orthogonal; the former specifies whether multiple words are
1378 potentially affected, the latter whether multiple substitutions can
1379 potentially occur within each affected word.
1387 are subjected to variable expansion before being parsed as
1388 regular expressions.
1390 Replaces each word in the variable with its last component.
1392 Remove adjacent duplicate words (like
1395 .It Cm \&:\&? Ar true_string Cm \&: Ar false_string
1397 If the variable name (not its value), when parsed as a .if conditional
1398 expression, evaluates to true, return as its value the
1400 otherwise return the
1402 Since the variable name is used as the expression, \&:\&? must be the
1403 first modifier after the variable name itself - which will, of course,
1404 usually contain variable expansions.
1405 A common error is trying to use expressions like
1406 .Dl ${NUMBERS:M42:?match:no}
1407 which actually tests defined(NUMBERS),
1408 to determine is any words match "42" you need to use something like:
1409 .Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} .
1410 .It Ar :old_string=new_string
1413 style variable substitution.
1414 It must be the last modifier specified.
1419 do not contain the pattern matching character
1421 then it is assumed that they are
1422 anchored at the end of each word, so only suffixes or entire
1423 words may be replaced.
1432 contains the pattern matching character
1436 matches, then the result is the
1440 contains the pattern matching character
1442 then it is not treated specially and it is printed as a literal
1445 If there is more than one pattern matching character
1451 only the first instance is treated specially (as the pattern character);
1452 all subsequent instances are treated as regular characters
1454 Variable expansion occurs in the normal fashion inside both
1458 with the single exception that a backslash is used to prevent the
1459 expansion of a dollar sign
1461 not a preceding dollar sign as is usual.
1463 .It Cm \&:@ Ar temp Cm @ Ar string Cm @
1465 This is the loop expansion mechanism from the OSF Development
1466 Environment (ODE) make.
1469 loops expansion occurs at the time of
1473 to each word in the variable and evaluate
1475 The ODE convention is that
1477 should start and end with a period.
1479 .Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
1481 However a single character variable is often more readable:
1482 .Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
1484 Save the current variable value in
1488 for later reference.
1490 .Bd -literal -offset indent
1491 M_cmpv.units = 1 1000 1000000
1492 M_cmpv = S,., ,g:_:range:@i@+ $${_:[-$$i]} \&\\
1493 \\* $${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh
1495 .Dv .if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}}
1500 is used to save the result of the
1502 modifier which is later referenced using the index values from
1504 .It Cm \&:U Ns Ar newval
1505 If the variable is undefined
1508 If the variable is defined, the existing value is returned.
1509 This is another ODE make feature.
1510 It is handy for setting per-target CFLAGS for instance:
1511 .Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
1512 If a value is only required if the variable is undefined, use:
1513 .Dl ${VAR:D:Unewval}
1514 .It Cm \&:D Ns Ar newval
1515 If the variable is defined
1519 The name of the variable is the value.
1521 The path of the node which has the same name as the variable
1523 If no such node exists or its path is null, then the
1524 name of the variable is used.
1525 In order for this modifier to work, the name (node) must at least have
1526 appeared on the rhs of a dependency.
1528 .It Cm \&:\&! Ar cmd Cm \&!
1530 The output of running
1534 If the variable is non-empty it is run as a command and the output
1535 becomes the new value.
1536 .It Cm \&::= Ns Ar str
1537 The variable is assigned the value
1540 This modifier and its variations are useful in
1541 obscure situations such as wanting to set a variable when shell commands
1543 These assignment modifiers always expand to
1544 nothing, so if appearing in a rule line by themselves should be
1545 preceded with something to keep
1551 helps avoid false matches with the
1555 modifier and since substitution always occurs the
1557 form is vaguely appropriate.
1558 .It Cm \&::?= Ns Ar str
1561 but only if the variable does not already have a value.
1562 .It Cm \&::+= Ns Ar str
1566 .It Cm \&::!= Ns Ar cmd
1567 Assign the output of
1570 .It Cm \&:\&[ Ns Ar range Ns Cm \&]
1571 Selects one or more words from the value,
1572 or performs other operations related to the way in which the
1573 value is divided into words.
1575 Ordinarily, a value is treated as a sequence of words
1576 delimited by white space.
1577 Some modifiers suppress this behavior,
1578 causing a value to be treated as a single word
1579 (possibly containing embedded white space).
1580 An empty value, or a value that consists entirely of white-space,
1581 is treated as a single word.
1582 For the purposes of the
1584 modifier, the words are indexed both forwards using positive integers
1585 (where index 1 represents the first word),
1586 and backwards using negative integers
1587 (where index \-1 represents the last word).
1591 is subjected to variable expansion, and the expanded result is
1592 then interpreted as follows:
1593 .Bl -tag -width index
1596 Selects a single word from the value.
1598 .It Ar start Ns Cm \&.. Ns Ar end
1599 Selects all words from
1606 selects all words from the second word to the last word.
1611 then the words are output in reverse order.
1614 selects all the words from last to first.
1615 If the list is already ordered, then this effectively reverses
1616 the list, but it is more efficient to use
1619 .Ql Cm \&:O:[-1..1] .
1622 Causes subsequent modifiers to treat the value as a single word
1623 (possibly containing embedded white space).
1624 Analogous to the effect of
1633 Causes subsequent modifiers to treat the value as a sequence of words
1634 delimited by white space.
1635 Analogous to the effect of
1640 Returns the number of words in the value.
1643 .Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
1644 Makefile inclusion, conditional structures and for loops reminiscent
1645 of the C programming language are provided in
1647 All such structures are identified by a line beginning with a single
1651 Files are included with either
1652 .Cm \&.include \&< Ns Ar file Ns Cm \&>
1654 .Cm \&.include \&\*q Ns Ar file Ns Cm \&\*q .
1655 Variables between the angle brackets or double quotes are expanded
1656 to form the file name.
1657 If angle brackets are used, the included makefile is expected to be in
1658 the system makefile directory.
1659 If double quotes are used, the including makefile's directory and any
1660 directories specified using the
1662 option are searched before the system
1664 For compatibility with other versions of
1666 .Ql include file ...
1669 If the include statement is written as
1673 then errors locating and/or opening include files are ignored.
1675 If the include statement is written as
1677 not only are errors locating and/or opening include files ignored,
1678 but stale dependencies within the included file will be ignored
1680 .Va .MAKE.DEPENDFILE .
1682 Conditional expressions are also preceded by a single dot as the first
1683 character of a line.
1684 The possible conditionals are as follows:
1686 .It Ic .error Ar message
1687 The message is printed along with the name of the makefile and line number,
1691 .It Ic .export Ar variable ...
1692 Export the specified global variable.
1693 If no variable list is provided, all globals are exported
1694 except for internal variables (those that start with
1696 This is not affected by the
1698 flag, so should be used with caution.
1699 For compatibility with other
1702 .Ql export variable=value
1705 Appending a variable name to
1707 is equivalent to exporting a variable.
1708 .It Ic .export-env Ar variable ...
1711 except that the variable is not appended to
1712 .Va .MAKE.EXPORTED .
1713 This allows exporting a value to the environment which is different from that
1717 .It Ic .export-literal Ar variable ...
1720 except that variables in the value are not expanded.
1721 .It Ic .info Ar message
1722 The message is printed along with the name of the makefile and line number.
1723 .It Ic .undef Ar variable
1724 Un-define the specified global variable.
1725 Only global variables may be un-defined.
1726 .It Ic .unexport Ar variable ...
1729 The specified global
1731 will be removed from
1732 .Va .MAKE.EXPORTED .
1733 If no variable list is provided, all globals are unexported,
1737 .It Ic .unexport-env
1738 Unexport all globals previously exported and
1739 clear the environment inherited from the parent.
1740 This operation will cause a memory leak of the original environment,
1741 so should be used sparingly.
1744 being 0, would make sense.
1745 Also note that any variables which originated in the parent environment
1746 should be explicitly preserved if desired.
1748 .Bd -literal -offset indent
1749 .Li .if ${.MAKE.LEVEL} == 0
1756 Would result in an environment containing only
1758 which is the minimal useful environment.
1761 will also be pushed into the new environment.
1762 .It Ic .warning Ar message
1763 The message prefixed by
1765 is printed along with the name of the makefile and line number.
1766 .It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ...
1767 Test the value of an expression.
1768 .It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1769 Test the value of a variable.
1770 .It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1771 Test the value of a variable.
1772 .It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1773 Test the target being built.
1774 .It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ...
1775 Test the target being built.
1777 Reverse the sense of the last conditional.
1778 .It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ...
1783 .It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1788 .It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1793 .It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1798 .It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1804 End the body of the conditional.
1809 may be any one of the following:
1810 .Bl -tag -width "Cm XX"
1816 of higher precedence than
1822 will only evaluate a conditional as far as is necessary to determine
1824 Parentheses may be used to change the order of evaluation.
1825 The boolean operator
1827 may be used to logically negate an entire
1829 It is of higher precedence than
1834 may be any of the following:
1835 .Bl -tag -width defined
1837 Takes a variable name as an argument and evaluates to true if the variable
1840 Takes a target name as an argument and evaluates to true if the target
1841 was specified as part of
1843 command line or was declared the default target (either implicitly or
1846 before the line containing the conditional.
1848 Takes a variable, with possible modifiers, and evaluates to true if
1849 the expansion of the variable would result in an empty string.
1851 Takes a file name as an argument and evaluates to true if the file exists.
1852 The file is searched for on the system search path (see
1855 Takes a target name as an argument and evaluates to true if the target
1858 Takes a target name as an argument and evaluates to true if the target
1859 has been defined and has commands associated with it.
1863 may also be an arithmetic or string comparison.
1864 Variable expansion is
1865 performed on both sides of the comparison, after which the integral
1866 values are compared.
1867 A value is interpreted as hexadecimal if it is
1868 preceded by 0x, otherwise it is decimal; octal numbers are not supported.
1869 The standard C relational operators are all supported.
1871 variable expansion, either the left or right hand side of a
1875 operator is not an integral value, then
1876 string comparison is performed between the expanded
1878 If no relational operator is given, it is assumed that the expanded
1879 variable is being compared against 0 or an empty string in the case
1880 of a string comparison.
1884 is evaluating one of these conditional expressions, and it encounters
1885 a (white-space separated) word it doesn't recognize, either the
1889 expression is applied to it, depending on the form of the conditional.
1897 expression is applied.
1898 Similarly, if the form is
1904 expression is applied.
1906 If the conditional evaluates to true the parsing of the makefile continues
1908 If it evaluates to false, the following lines are skipped.
1909 In both cases this continues until a
1915 For loops are typically used to apply a set of rules to a list of files.
1916 The syntax of a for loop is:
1918 .Bl -tag -compact -width Ds
1919 .It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression
1926 is evaluated, it is split into words.
1927 On each iteration of the loop, one word is taken and assigned to each
1931 are substituted into the
1933 inside the body of the for loop.
1934 The number of words must come out even; that is, if there are three
1935 iteration variables, the number of words provided must be a multiple
1938 Comments begin with a hash
1940 character, anywhere but in a shell
1941 command line, and continue to the end of an unescaped new line.
1942 .Sh SPECIAL SOURCES (ATTRIBUTES)
1943 .Bl -tag -width .IGNOREx
1945 Target is never out of date, but always execute commands anyway.
1947 Ignore any errors from the commands associated with this target, exactly
1948 as if they all were preceded by a dash
1950 .\" .It Ic .INVISIBLE
1955 Mark all sources of this target as being up-to-date.
1957 Execute the commands associated with this target even if the
1961 options were specified.
1962 Normally used to mark recursive
1965 Create a meta file for the target, even if it is flagged as
1970 Usage in conjunction with
1972 is the most likely case.
1973 In "meta" mode, the target is out-of-date if the meta file is missing.
1975 Do not create a meta file for the target.
1976 Meta files are also not created for
1983 Ignore differences in commands when deciding if target is out of date.
1984 This is useful if the command contains a value which always changes.
1985 If the number of commands change, though, the target will still be out of date.
1986 The same effect applies to any command line that uses the variable
1988 which can be used for that purpose even when not otherwise needed or desired:
1989 .Bd -literal -offset indent
1991 skip-compare-for-some:
1992 @echo this will be compared
1993 @echo this will not ${.OODATE:M.NOMETA_CMP}
1994 @echo this will also be compared
1999 pattern suppresses any expansion of the unwanted variable.
2001 Do not search for the target in the directories specified by
2006 selects the first target it encounters as the default target to be built
2007 if no target was specified.
2008 This source prevents this target from being selected.
2010 If a target is marked with this attribute and
2012 can't figure out how to create it, it will ignore this fact and assume
2013 the file isn't needed or already exists.
2016 correspond to an actual file; it is always considered to be out of date,
2017 and will not be created with the
2020 Suffix-transformation rules are not applied to
2026 is interrupted, it normally removes any partially made targets.
2027 This source prevents the target from being removed.
2032 Do not echo any of the commands associated with this target, exactly
2033 as if they all were preceded by an at sign
2036 Turn the target into
2039 When the target is used as a source for another target, the other target
2040 acquires the commands, sources, and attributes (except for
2044 If the target already has commands, the
2046 target's commands are appended
2053 target commands to the target.
2057 appears in a dependency line, the sources that precede it are
2058 made before the sources that succeed it in the line.
2059 Since the dependents of files are not made until the file itself
2060 could be made, this also stops the dependents being built unless they
2061 are needed for another branch of the dependency tree.
2074 the output is always
2080 The ordering imposed by
2082 is only relevant for parallel makes.
2085 Special targets may not be included with other targets, i.e. they must be
2086 the only target specified.
2087 .Bl -tag -width .BEGINx
2089 Any command lines attached to this target are executed before anything
2094 rule for any target (that was used only as a
2097 can't figure out any other way to create.
2098 Only the shell script is used.
2101 variable of a target that inherits
2104 to the target's own name.
2105 .It Ic .DELETE_ON_ERROR
2106 If this target is present in the makefile, it globally causes make to
2107 delete targets whose commands fail.
2108 (By default, only targets whose commands are interrupted during
2109 execution are deleted.
2110 This is the historical behavior.)
2111 This setting can be used to help prevent half-finished or malformed
2112 targets from being left around and corrupting future rebuilds.
2114 Any command lines attached to this target are executed after everything
2117 Any command lines attached to this target are executed when another target fails.
2120 variable is set to the target that failed.
2122 .Ic MAKE_PRINT_VAR_ON_ERROR .
2124 Mark each of the sources with the
2127 If no sources are specified, this is the equivalent of specifying the
2133 is interrupted, the commands for this target will be executed.
2135 If no target is specified when
2137 is invoked, this target will be built.
2139 This target provides a way to specify flags for
2141 when the makefile is used.
2142 The flags are as if typed to the shell, though the
2146 .\" XXX: NOT YET!!!!
2147 .\" .It Ic .NOTPARALLEL
2148 .\" The named targets are executed in non parallel mode.
2149 .\" If no targets are
2150 .\" specified, then all targets are executed in non parallel mode.
2154 attribute to any specified sources.
2156 Disable parallel mode.
2160 for compatibility with other pmake variants.
2162 The source is a new value for
2168 to it and update the value of
2171 The named targets are made in sequence.
2172 This ordering does not add targets to the list of targets to be made.
2173 Since the dependents of a target do not get built until the target itself
2174 could be built, unless
2176 is built by another part of the dependency graph,
2177 the following is a dependency loop:
2183 The ordering imposed by
2185 is only relevant for parallel makes.
2186 .\" XXX: NOT YET!!!!
2187 .\" .It Ic .PARALLEL
2188 .\" The named targets are executed in parallel mode.
2189 .\" If no targets are
2190 .\" specified, then all targets are executed in parallel mode.
2192 The sources are directories which are to be searched for files not
2193 found in the current directory.
2194 If no sources are specified, any previously specified directories are
2196 If the source is the special
2198 target, then the current working
2199 directory is searched last.
2200 .It Ic .PATH. Ns Va suffix
2203 but applies only to files with a particular suffix.
2204 The suffix must have been previously declared with
2209 attribute to any specified sources.
2213 attribute to any specified sources.
2214 If no sources are specified, the
2216 attribute is applied to every
2221 will use to execute commands.
2222 The sources are a set of
2225 .Bl -tag -width hasErrCtls
2227 This is the minimal specification, used to select one of the built-in
2234 Specifies the path to the shell.
2236 Indicates whether the shell supports exit on error.
2238 The command to turn on error checking.
2240 The command to disable error checking.
2242 The command to turn on echoing of commands executed.
2244 The command to turn off echoing of commands executed.
2246 The output to filter after issuing the
2249 It is typically identical to
2252 The flag to pass the shell to enable error checking.
2254 The flag to pass the shell to enable command echoing.
2256 The string literal to pass the shell that results in a single newline
2257 character when used outside of any quoting characters.
2261 \&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e
2262 check="set \-e" ignore="set +e" \e
2263 echo="set \-v" quiet="set +v" filter="set +v" \e
2264 echoFlag=v errFlag=e newline="'\en'"
2269 attribute to any specified sources.
2270 If no sources are specified, the
2272 attribute is applied to every
2273 command in the file.
2275 This target gets run when a dependency file contains stale entries, having
2277 set to the name of that dependency file.
2279 Each source specifies a suffix to
2281 If no sources are specified, any previously specified suffixes are deleted.
2282 It allows the creation of suffix-transformation rules.
2288 cc \-o ${.TARGET} \-c ${.IMPSRC}
2293 uses the following environment variables, if they exist:
2299 .Ev MAKEOBJDIRPREFIX ,
2305 .Ev MAKEOBJDIRPREFIX
2308 may only be set in the environment or on the command line to
2310 and not as makefile variables;
2311 see the description of
2315 .Bl -tag -width /usr/share/mk -compact
2317 list of dependencies
2319 list of dependencies
2321 list of dependencies
2325 system makefile directory
2328 The basic make syntax is compatible between different versions of make;
2329 however the special variables, variable modifiers and conditionals are not.
2331 An incomplete list of changes in older versions of
2334 The way that .for loop variables are substituted changed after
2336 so that they still appear to be variable expansions.
2337 In particular this stops them being treated as syntax, and removes some
2338 obscure problems using them in .if statements.
2340 The way that parallel makes are scheduled changed in
2342 so that .ORDER and .WAIT apply recursively to the dependent nodes.
2343 The algorithms used may change again in the future.
2344 .Ss Other make dialects
2345 Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not
2346 support most of the features of
2348 as described in this manual.
2350 .Bl -bullet -offset indent
2356 declarations and most functionality pertaining to parallelization.
2357 (GNU make supports parallelization but lacks these features needed to
2358 control it effectively.)
2360 Directives, including for loops and conditionals and most of the
2361 forms of include files.
2362 (GNU make has its own incompatible and less powerful syntax for
2365 All built-in variables that begin with a dot.
2367 Most of the special sources and targets that begin with a dot,
2368 with the notable exception of
2374 Variable modifiers, except for the
2376 string substitution, which does not portably support globbing with
2378 and historically only works on declared suffixes.
2382 variable even in its short form; most makes support this functionality
2383 but its name varies.
2386 Some features are somewhat more portable, such as assignment with
2393 functionality is based on an older feature
2395 found in GNU make and many versions of SVR4 make; however,
2396 historically its behavior is too ill-defined (and too buggy) to rely
2403 variables are more or less universally portable, as is the
2406 Basic use of suffix rules (for files only in the current directory,
2407 not trying to chain transformations together, etc.) is also reasonably
2413 is derived from NetBSD
2415 It uses autoconf to facilitate portability to other platforms.
2423 implementation is based on Adam De Boor's pmake program which was written
2424 for Sprite at Berkeley.
2425 It was designed to be a parallel distributed make running jobs on different
2426 machines using a daemon called
2429 Historically the target/dependency
2431 has been used to FoRCe rebuilding (since the target/dependency
2432 does not exist... unless someone creates an
2438 syntax is difficult to parse without actually acting on the data.
2439 For instance, finding the end of a variable's use should involve scanning
2440 each of the modifiers, using the correct terminator for each field.
2443 just counts {} and () in order to find the end of a variable expansion.
2445 There is no way of escaping a space character in a filename.