1MAKE(1)                     General Commands Manual                    MAKE(1)
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NAME

6       make - maintain program groups
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SYNOPSIS

9       make [ -f makefile ] [ option ] ...  file ...
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DESCRIPTION

12       Make  executes commands in makefile to update one or more target names.
13       Name is typically a program.  If no -f option  is  present,  `makefile'
14       and  `Makefile'  are  tried in order.  If makefile is `-', the standard
15       input is taken.  More than one -f option may appear
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17       Make updates a target if it depends on  prerequisite  files  that  have
18       been modified since the target was last modified, or if the target does
19       not exist.
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21       Makefile contains a sequence of entries that specify dependencies.  The
22       first  line  of  an  entry is a blank-separated list of targets, then a
23       colon, then a list of prerequisite files.  Text following a  semicolon,
24       and all following lines that begin with a tab, are shell commands to be
25       executed to update the target.
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27       Sharp and newline surround comments.
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29       The following makefile says that `pgm' depends on two files  `a.o'  and
30       `b.o',  and  that  they  in turn depend on `.c' files and a common file
31       `incl'.
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34                     pgm: a.o b.o
35                     cc a.o b.o -lm -o pgm
36              a.o: incl a.c
37                     cc -c a.c
38              b.o: incl b.c
39                     cc -c b.c
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41       Makefile entries of the form
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43              string1 = string2
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45       are  macro  definitions.   Subsequent  appearances  of  $(string1)  are
46       replaced by string2.  If string1 is a single character, the parentheses
47       are optional.
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49       Make infers prerequisites for files for which makefile  gives  no  con‐
50       struction  commands.   For example, a `.c' file may be inferred as pre‐
51       requisite for a `.o' file and be compiled to  produce  the  `.o'  file.
52       Thus the preceding example can be done more briefly:
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55                     pgm: a.o b.o
56                     cc a.o b.o -lm -o pgm
57              a.o b.o: incl
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59       Prerequisites are inferred according to selected suffixes listed as the
60       `prerequisites' for the special name `.SUFFIXES'; multiple lists  accu‐
61       mulate;  an  empty list clears what came before.  Order is significant;
62       the first possible name for which both a file and a rule  as  described
63       in the next paragraph exist is inferred.  The default list is
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65              .SUFFIXES: .out .o .c .e .r .f .y .l .s
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67       The  rule  to  create a file with suffix s2 that depends on a similarly
68       named file with suffix s1 is specified as an  entry  for  the  `target'
69       s1s2.   In  such  an  entry, the special macro $* stands for the target
70       name with suffix deleted, $@ for the full target name, $< for the  com‐
71       plete  list of prerequisites, and $? for the list of prerequisites that
72       are out of date.  For example, a rule for making optimized  `.o'  files
73       from `.c' files is
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75              .c.o: ; cc -c -O -o $@ $*.c
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77       Certain  macros  are used by the default inference rules to communicate
78       optional arguments  to  any  resulting  compilations.   In  particular,
79       `CFLAGS'  is  used for cc and f77(1) options, `LFLAGS' and `YFLAGS' for
80       lex and yacc(1) options.
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82       Command lines are executed one at a time, each by  its  own  shell.   A
83       line is printed when it is executed unless the special target `.SILENT'
84       is in makefile, or the first character of the command is `@'.
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86       Commands returning nonzero status (see intro(1)) cause make  to  termi‐
87       nate  unless the special target `.IGNORE' is in makefile or the command
88       begins with <tab><hyphen>.
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90       Interrupt and quit cause the target to be  deleted  unless  the  target
91       depends on the special name `.PRECIOUS'.
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93       Other options:
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95       -i     Equivalent to the special entry `.IGNORE:'.
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97       -k     When  a command returns nonzero status, abandon work on the cur‐
98              rent entry, but continue on branches that do not depend  on  the
99              current entry.
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101       -n     Trace  and  print,  but  do  not  execute the commands needed to
102              update the targets.
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104       -t     Touch, i.e. update the modified date of targets, without execut‐
105              ing any commands.
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107       -r     Equivalent  to  an  initial  special  entry `.SUFFIXES:' with no
108              list.
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110       -s     Equivalent to the special entry `.SILENT:'.
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FILES

113       makefile, Makefile
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SEE ALSO

116       sh(1), touch(1)
117       S. I. Feldman Make - A Program for Maintaining Computer Programs
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BUGS

120       Some commands return nonzero status inappropriately.  Use -i  to  over‐
121       come the difficulty.
122       Commands  that  are  directly executed by the shell, notably cd(1), are
123       ineffectual across newlines in make.
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