Intel XENIX 286 Programmers Guide (86) - Tenox.tc

XENIX Programming make: Program Maintainer
If a change to a file is absolutely certain to be benign (e.g., adding a new definition to
an include file), the -t (touch) option can save a lot of time: instead of issuing a large
nu mber of superfluous recompilations, make updates the modification times on the
affected file. Thus, the command
make -ts
which stands for touch silently, causes the relevant files to appear up to date.
The debugging option -d causes make to print out a very detailed description of what it
is doing, including the file times. The output is verbose and is recommended only as a
last resort.
Using make: An Example
As an example of the use of make, examine the makefile used to maintain the make
program itself. The code for make is spread over a number of C source files and a yacc
grammar.
#Description fi le for the make command
# Macro definiti ons below
P = lpr
FILES = Makefile vers.c defs main.c doname.c misc.c files.c dosys.c\
gram.y lex.c
OBJECTS = vers.o main.o ... dosys.o gram.o
LIBES =
LINT = lint -p
CFLAGS = -0
#targets: dependents
##ITAB > actions
make: ${OBJECTS)
cc $(CFLAGS) $(OBJECTS) $(LIBES) -o make
size make
${OBJECTS): defs
gram.o: lex.c
cleanup:
-rm *.o gram.c
-du
install:
@size make /usr/bin/make
cp make /usr/bin/make ; rm make
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