Program as a single file

• testfac.c

Program created as five s eparate files

• myinclude.h
• main.c
• input.c
• factorial.c
• output.c

Compile as one file and execute

• cat myinclude.h main.c input.c factorial.c output.c > total.c
• gcc -o testfact total.c
• ./testfact
• cis-lclient20:~/2012/c/make>gcc total.c
• cis-lclient20:~/2012/c/make>a.out
  input a number - 5
  The length of f is 1
  The factorial is 120
• cis-lclient20:~/2012/c/make>a.out
  input a number - 10
  The length of f is 1
  The factorial is 0
  

Compile each file separately to create four object files, then link into an executable

• gcc -c input.c
• gcc -c output.c
• gcc -c factorial.c
• gcc -c main.c
• ls *.o
  factorial.o input.o main.o output.o
• gcc -o testfac main.o input.o factorial.o output.o
• ./testfac
  input a number - 5
  The length of f is 1
  The factorial is 120

Use a shell script to compile each file separately

• cis-lclient06:~/2012/c/make>more shellscript
  #!/bin/sh
  # remember "chmod 755 your-script-name"
  gcc -c input.c # produces input.o
  gcc -c output.c # produces output.o
  gcc -c factorial.c # products factorial.o
  gcc -c main.c # produces main.o
  gcc -o testfac main.o input.o factorial.o output.o
  ./testfac
• cis-lclient06:~/2012/c/make>ls *.o
  ls: No match.
• cis-lclient06:~/2012/c/make>shellscript
  input a number - 5
  The length of f is 1
  The factorial is 120
• cis-lclient06:~/2012/c/make>ls *.o
  factorial.o input.o main.o output.o
  

makefile to compile and link, long version

• cis-lclient20:~/2012/c/make>more makefile1
  testfac: main.o input.o factorial.o output.o
  gcc main.o input.o factorial.o output.o -o testfac
  # gcc main.o input.o factorial.o output.o -o $@

main.o: main.c myinclude.h
gcc -c main.c

input.o: input.c myinclude.h
gcc -c input.c

factorial.o: factorial.c myinclude.h
$(CC) -c factorial.c

output.o: output.c myinclude.h
$(CC) -c output.c
clean:
-rm -f *.o testfac core
all:
gcc -c main.c input.c factorial.c output.c
gcc main.o input.o factorial.o output.o -o testfac

makefile to compile and link

cis-lclient20:~/2012/c/make>more makefile

OBJ = main.o input.o factorial.o output.o
SOURCE = main.c input.c factorial.c output.c
CC = gcc
testfac: ${OBJ}
${CC} -o $@ ${OBJ}

main.o: myinclude.h

input.o: myinclude.h

factorial.o: myinclude.h

output.o: myinclude.h

clean:
-rm -f *.o testfac core
all:
gcc -c ${SOURCE}
gcc -o testfac ${OBJ}
cis-lclient20:~/2012/c/make>

Executing the makefile

cis-lclient20:~/2012/c/make>make clean
rm -f *.o testfac core
cis-lclient20:~/2012/c/make>make
gcc -c -o main.o main.c
gcc -c -o input.o input.c
gcc -c -o factorial.o factorial.c
gcc -c -o output.o output.c
gcc -o testfac main.o input.o factorial.o output.o
cis-lclient20:~/2012/c/make>make
make: `testfac' is up to date.
cis-lclient20:~/2012/c/make>testfac
input a number - 5
The length of f is 1
The factorial is 120

Change char to long long

• cis-lclient20:~/2012/c/make>nano myinclude.h
  /* my include file */
  #include <stdio.h>
  #define INTTYPE unsigned long long
  INTTYPE factorial(INTTYPE);
  INTTYPE input();
  void output(INTTYPE);
• cis-lclient20:~/2012/c/make>make
  gcc -c -o main.o main.c
  gcc -c -o input.o input.c
  gcc -c -o factorial.o factorial.c
  gcc -c -o output.o output.c
  gcc -o testfac main.o input.o factorial.o output.o
• cis-lclient20:~/2012/c/make>testfac
  input a number - 20
  The length of f is 8
  The factorial is 2432902008176640000
• cis-lclient20:~/2012/c/make>