man(1) Manual page archive

     USGMAKE(1)                                             USGMAKE(1)

          usgmake - maintain, update, and regenerate groups of

          usgmake [-f makefile] [-p] [-i] [-k] [-s] [-r] [-n] [-b]
          [-e] [-m] [-t] [-d] [-q] [names]

          The following is a brief description of all options and some
          special names:

          -f makefile  Description file name.  Makefile is assumed to
                       be the name of a description file.  A file name
                       of - denotes the standard input.  The contents
                       of makefile override the built-in rules if they
                       are present.

          -p           Print out the complete set of macro definitions
                       and target descriptions.

          -i           Ignore error codes returned by invoked com-
                       mands.  This mode is entered if the fake target
                       name .IGNORE appears in the description file.

          -k           Abandon work on the current entry, but continue
                       on other branches that do not depend on that

          -s           Silent mode.  Do not print command lines before
                       executing.  This mode is also entered if the
                       fake target name .SILENT appears in the
                       description file.

          -r           Do not use the built-in rules.

          -n           No execute mode.  Print commands, but do not
                       execute them.  Even lines beginning with an @
                       are printed.

          -b           Compatibility mode for old makefiles.

          -e           Environment variables override assignments
                       within makefiles.

          -m           Print a memory map showing text, data, and
                       stack.  This option is a no-operation on sys-
                       tems without the getu system call.

          -t           Touch the target files (causing them to be up-

     USGMAKE(1)                                             USGMAKE(1)

                       to-date) rather than issue the usual commands.

          -d           Debug mode.  Print out detailed information on
                       files and times examined.

          -q           Question.  The make command returns a zero or
                       non-zero status code depending on whether the
                       target file is or is not up-to-date.

          .DEFAULT     If a file must be made but there are no
                       explicit commands or relevant built-in rules,
                       the commands associated with the name .DEFAULT
                       are used if it exists.

          .PRECIOUS    Dependents of this target will not be removed
                       when quit or interrupt are hit.

          .SILENT      Same effect as the -s option.

          .IGNORE      Same effect as the -i option.

          Make executes commands in makefile to update one or more
          target names. Name is typically a program.  If no -f option
          is present, makefile, Makefile, s.makefile, and s.Makefile
          are tried in order.  If makefile is -, the standard input is
          taken.  More than one - makefile argument pair may appear.

          Make updates a target only if it depends on files that are
          newer than the target.  All prerequisite files of a target
          are added recursively to the list of targets.  Missing files
          are deemed to be out of date.

          Makefile contains a sequence of entries that specify depen-
          dencies.  The first line of an entry is a blank-separated,
          non-null list of targets, then a :, then a (possibly null)
          list of prerequisite files or dependencies.  Text following
          a ; and all following lines that begin with a tab are shell
          commands to be executed to update the target.  The first
          line that does not begin with a tab or # begins a new depen-
          dency or macro definition.  Shell commands may be continued
          across lines with the <backslash><new-line> sequence.
          Everything printed by make (except the initial tab) is
          passed directly to the shell as is.  Thus,

               echo a\

          will produce


          exactly the same as the shell would.

     USGMAKE(1)                                             USGMAKE(1)

          Sharp (#) and new-line surround comments.

          The following makefile says that pgm depends on two files
          a.o and b.o, and that they in turn depend on their corre-
          sponding source files (a.c and b.c) and a common file

               pgm: a.o b.o
                    cc a.o b.o -o pgm
               a.o: incl.h a.c
                    cc -c a.c
               b.o: incl.h b.c
                    cc -c b.c

          Command lines are executed one at a time, each by its own
          shell.  The first one or two characters in a command can be
          the following: -, @, -@, or @-.  If @ is present, printing
          of the command is suppressed.  If - is present, make ignores
          an error.  A line is printed when it is executed unless the
          -s option is present, or the entry .SILENT: is in makefile,
          or unless the initial character sequence contains a @.  The
          -n option specifies printing without execution; however, if
          the command line has the string $(MAKE) in it, the line is
          always executed (see discussion of the MAKEFLAGS macro under
          Environment). The -t (touch) option updates the modified
          date of a file without executing any commands.

          Commands returning non-zero status normally terminate make.
          If the -i option is present, or the entry .IGNORE: appears
          in makefile, or the initial character sequence of the com-
          mand contains -.  the error is ignored.  If the -k option is
          present, work is abandoned on the current entry, but contin-
          ues on other branches that do not depend on that entry.

          The -b option allows old makefiles (those written for the
          old version of make) to run without errors.  The difference
          between the old version of make and this version is that
          this version requires all dependency lines to have a (possi-
          bly null or implicit) command associated with them.  The
          previous version of make assumed if no command was specified
          explicitly that the command was null.

          Interrupt and quit cause the target to be deleted unless the
          target is a dependency of the special name .PRECIOUS.

          The environment is read by make.  All variables are assumed
          to be macro definitions and processed as such.  The environ-
          ment variables are processed before any makefile and after
          the internal rules; thus, macro assignments in a makefile
          override environment variables.  The -e option causes the
          environment to override the macro assignments in a makefile.

     USGMAKE(1)                                             USGMAKE(1)

          The MAKEFLAGS environment variable is processed by make as
          containing any legal input option (except -f, -p, and -d)
          defined for the command line.  Further, upon invocation,
          make ``invents'' the variable if it is not in the environ-
          ment, puts the current options into it, and passes it on to
          invocations of commands.  Thus, MAKEFLAGS always contains
          the current input options.  This proves very useful for
          ``super-makes''.  In fact, as noted above, when the -n
          option is used, the command $(MAKE) is executed anyway;
          hence, one can perform a make -n recursively on a whole
          software system to see what would have been executed.  This
          is because the -n is put in MAKEFLAGS and passed to further
          invocations of $(MAKE).  This is one way of debugging all of
          the makefiles for a software project without actually doing

          Entries of the form string1 = string2 are macro definitions.
          String2 is defined as all characters up to a comment charac-
          ter or an unescaped newline.  Subsequent appearances of
          $(string1[:subst1=[subst2]]) are replaced by string2. The
          parentheses are optional if a single character macro name is
          used and there is no substitute sequence.  The optional
          :subst1=subst2 is a substitute sequence.  If it is speci-
          fied, all non-overlapping occurrences of subst1 in the named
          macro are replaced by subst2.  Strings (for the purposes of
          this type of substitution) are delimited by blanks, tabs,
          new-line characters, and beginnings of lines.  An example of
          the use of the substitute sequence is shown under Libraries.

        Internal Macros
          There are five internally maintained macros which are useful
          for writing rules for building targets.

          $*   The macro $* stands for the file name part of the cur-
               rent dependent with the suffix deleted.  It is evalu-
               ated only for inference rules.

          $@   The $@ macro stands for the full target name of the
               current target.  It is evaluated only for explicitly
               named dependencies.

          $<   The $< macro is only evaluated for inference rules or
               the .DEFAULT rule.  It is the module which is out of
               date with respect to the target (i.e., the ``manufac-
               tured'' dependent file name).  Thus, in the .c.o rule,
               the $< macro would evaluate to the .c file.  An example
               for making optimized .o files from .c files is:

                         cc -c -O $*.c

     USGMAKE(1)                                             USGMAKE(1)


                         cc -c -O $<

          $?   The $? macro is evaluated when explicit rules from the
               makefile are evaluated.  It is the list of prerequi-
               sites that are out of date with respect to the target;
               essentially, those modules which must be rebuilt.

          $%   The $% macro is only evaluated when the target is an
               archive library member of the form lib(file.o).  In
               this case, $@ evaluates to lib and $% evaluates to the
               library member, file.o.

          Four of the five macros can have alternative forms.  When an
          upper case D or F is appended to any of the four macros the
          meaning is changed to ``directory part'' for D and ``file
          part'' for F.  Thus, $(@D) refers to the directory part of
          the string $@.  If there is no directory part, The only
          macro excluded from this alternative form is $?.  The rea-
          sons for this are debatable.

          Certain names (for instance, those ending with .o) have
          inferable prerequisites such as .c, .s, etc.  If no update
          commands for such a file appear in makefile, and if an
          inferable prerequisite exists, that prerequisite is compiled
          to make the target.  In this case, make has inference rules
          which allow building files from other files by examining the
          suffixes and determining an appropriate inference rule to
          use.  The current default inference rules are:

               .c .c~ .sh .sh~ .c.o .c~.o .c~.c .s.o .s~.o .y.o .y~.o
               .l.o .l~.o
               .y.c .y~.c .l.c .c.a .c~.a .s~.a .h~.h

          The internal rules for make are contained in the source file
          rules.c for the make program.  These rules can be locally
          modified.  To print out the rules compiled into the make on
          any machine in a form suitable for recompilation, the fol-
          lowing command is used:

               make -fp - 2>/dev/null </dev/null

          The only peculiarity in this output is the (null) string
          which printf(3S) prints when handed a null string.

          A tilde in the above rules refers to an SCCS file (see
          sccsfile(5)). Thus, the rule .c~.o would transform an SCCS C
          source file into an object file (.o).  Because the s. of the
          SCCS files is a prefix it is incompatible with make's suffix

     USGMAKE(1)                                             USGMAKE(1)

          point-of-view.  Hence, the tilde is a way of changing any
          file reference into an SCCS file reference.

          A rule with only one suffix (i.e. .c:) is the definition of
          how to build x from x.c.  In effect, the other suffix is
          null.  This is useful for building targets from only one
          source file (e.g., shell procedures, simple C programs).

          Additional suffixes are given as the dependency list for
          .SUFFIXES.  Order is significant; the first possible name
          for which both a file and a rule exist is inferred as a pre-
          requisite.  The default list is:

               .SUFFIXES: .o .c .y .l .s

          Here again, the above command for printing the internal
          rules will display the list of suffixes implemented on the
          current machine.  Multiple suffix lists accumulate; .SUF-
          FIXES: with no dependencies clears the list of suffixes.

        Inference Rules
          The first example can be done more briefly:

               pgm: a.o b.o
                    cc a.o b.o -o pgm
               a.o b.o: incl.h

          This is because make has a set of internal rules for build-
          ing files.  The user may add rules to this list by simply
          putting them in the makefile.

          Certain macros are used by the default inference rules to
          permit the inclusion of optional matter in any resulting
          commands.  For example, CFLAGS, LFLAGS, and YFLAGS are used
          for compiler options to cc(1), lex(1), and yacc(1) respec-
          tively.  Again, the previous method for examining the cur-
          rent rules is recommended.

          The inference of prerequisites can be controlled.  The rule
          to create a file with suffix .o from a file with suffix .c
          is specified as an entry with .c.o: as the target and no
          dependents.  Shell commands associated with the target
          define the rule for making a .o file from a .c file.  Any
          target that has no slashes in it and starts with a dot is
          identified as a rule and not a true target.

          If a target or dependency name contains parenthesis, it is
          assumed to be an archive library, the string within paren-
          thesis referring to a member within the library.  Thus
          lib(file.o) and $(LIB)(file.o) both refer to an archive
          library which contains file.o. (This assumes the LIB macro

     USGMAKE(1)                                             USGMAKE(1)

          has been previously defined.)  The expression $(LIB)(file1.o
          file2.o) is not legal.  Rules pertaining to archive
          libraries have the form .XX.a where the XX is the suffix
          from which the archive member is to be made.  An unfortunate
          byproduct of the current implementation requires the XX to
          be different from the suffix of the archive member.  Thus,
          one cannot have lib(file.o) depend upon file.o explicitly.
          The most common use of the archive interface follows.  Here,
          we assume the source files are all C type source:

               lib: lib(file1.o) lib(file2.o) lib(file3.o)
                    @echo lib is now up to date
                    $(CC) -c $(CFLAGS) $<
                    ar rv $@ $*.o
                    rm -f $*.o

          In fact, the .c.a rule listed above is built into make and
          is unnecessary in this example.  A more interesting, but
          more limited example of an archive library maintenance con-
          struction follows:

               lib: lib(file1.o) lib(file2.o) lib(file3.o)
                    $(CC) -c $(CFLAGS) $(?:.o=.c)
                    ar rv lib $?
                    rm $?  @echo lib is now up to date

          Here the substitution mode of the macro expansions is used.
          The $?  list is defined to be the set of object file names
          (inside lib) whose C source files are out of date.  The sub-
          stitution mode translates the .o to .c.  (Unfortunately, one
          cannot as yet transform to .c~; however, this may become
          possible in the future.)  Note also, the disabling of the
          .c.a: rule, which would have created each object file, one
          by one.  This particular construct speeds up archive library
          maintenance considerably.  This type of construct becomes
          very cumbersome if the archive library contains a mix of
          assembly programs and C programs.

          [Mm]akefile and s.[Mm]akefile

          sh(1), mk(8).
          Make-A Program for Maintaining Computer Programs by S. I.
          An Augmented Version of Make by E. G. Bradford.

          Some commands return non-zero status inappropriately; use -i
          to overcome the difficulty.  Commands that are directly

     USGMAKE(1)                                             USGMAKE(1)

          executed by the shell, notably cd(1), are ineffectual across
          new-lines in make. The syntax (lib(file1.o file2.o file3.o)
          is illegal.  You cannot build lib(file.o) from file.o.  The
          macro $(a:.o=.c~) doesn't work.