Working with the Unix OS

Development Tools
Make looks at the date stamps on your files, then does what is necessary to create an up-to-date version.
Makefile format:
target: prerequisite-list
construction-commands
Increases of the modularity of programs means that a project may have to cope with a large number of files:
- file-to-file dependencies
- make creates the finished program by recompiling only those portions directly of indirectly affected by the
change
- find the target in the description file
- ensure that all files on which the target depends, exists and are up to date
- create target file if any of the generators have been modified more recently than the target
Commands in the rule will be performed whenever "main.o" is needed and "main.c" or "win.h" have been updated
since "main.o" was last rebuilt.
/* main.c ---------------------------*/
#include "win.h"
...
/* win.c ----------------------------*/
#include "win.h"
...
/* kit.c ----------------------------*/
#include "kit.h" #include "win.h"
...
# makefile --------------------------
prog: main.o win.a kit.a
cc -o prog main.a win.a kit.a #link
main.a: main.c win.h
cc -c main.c
win.o: win.c win.h
cc -c win.c -1curses
# compile
# compile in library
kit.a: kit.c kit.h win.h
cc -DDEBUG -c kit.c
# compile with debug
# -----------------------------------
$ make kit.o # recompiles kit.a if any of kit.c, kit.h or win.h has been changed
$ make prog # rebuilds (compiles) any of object files required to build "prog " and then link these files
$ make # same as "make prog" (1st rule)
$ make -n prog # show commands only (not performed)
$ make -ffile.mk # use file.mk instead of Makefile
Dependency Tree
main.c
win.c
win.h
main.o
win.o
prog
kit.c
kit.o
kit.h
# Makefile ----------------------------------------
BASE = /staff/neville
CC
= cc
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