Make and makefile

 

Makefile and makefile are equivalent.

$ MV makefile
$ Make
Gcc-C main. c
Gcc-C Liu. c
Gcc-C generatedatafile. c
Gcc-G main. O Liu. O generatedatafile. O-o Liu
-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ
Rm-f *. o

Makefile format

<Target 1>: Depend <Command 1> <Command 2>

MAKEFILE file format -------- use the section (rule) as the basic structure

$ Cat makefile Libs =-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ ALL: Liu Clean Two sections of all depend Liu: Main. O Liu. o Generatedatafile. o Liu depend Gcc-G $? -O $ @ $ (libs) Main. O: Main. c Gcc-C $? You must have a tab (that is, the tab key) Liu. O: Liu. c Gcc-C Liu. c Generatedatafile. O: generatedatafile. c Gcc-C $? Clean: $ (RM) *. o

 
The command line must use a tab and cannot contain a string of spaces.

Tab is the flag of the command line.

[MACG @ localhost mysqltmp] $ more makefile Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu-L/usr/lib/MySQL-l Mysqlclient-LZ Main. O: Main. c comm. h Gcc-C main. c Liu. O: Liu. c/usr/include/MySQL. h Gcc-C Liu. c Generatedatafile. O: generatedatafile. c Gcc-C generatedatafile. c

Only make a single section

$ Make main. o Gcc-C main. c

Main. O: Main. c Gcc-C $?

Make install and make
Clean is also a single section

# Cat makefile ... Install: ... Clean: ...

Menu-based Section

Reference, written directly at depend

$ VI makefile Libs =-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Liu: Main. o Liu. O generatedatafile. O clean Gcc-G main. O Liu. O generatedatafile. O-o Liu $ (Libs) Liu depend: Main. O Liu. o Generatedatafile. O clean Main. O: Main. c Gcc-C main. c Liu. O: Liu. c Gcc-C Liu. c Generatedatafile. O: generatedatafile. c Gcc-C generatedatafile. c Clean: $ (RM) *. o

$ Make Gcc-C main. c Gcc-C Liu. c Gcc-C generatedatafile. c Rm-f *. o Gcc-G main. O Liu. O generatedatafile. O-o Liu -L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ GCC: Main. O: no such file or Directory GCC: Liu. O: no such file or Directory

Because the overall execution sequence: O depend Conclusion 1, O depend Conclusion 2, O depend Conclusion 3, O Depend Summary 4 (clean ), O gcc-G main. O Liu. o Generatedatafile. O-o Liu $ (libs) So before GCC link, the *. O is deleted first, so an error occurs.

Correct practice $ VI makefile Libs =-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ ALL: Liu clean Set a general menu bar O The first step is to compile and link is to compile O The last step is deleted. Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu $ (libs) Main. O: Main. c Gcc-C main. c Liu. O: Liu. c Gcc-C Liu. c Generatedatafile. O: generatedatafile. c Gcc-C generatedatafile. c Clean: $ (RM) *. o

$ Make Gcc-C main. c Gcc-C Liu. c Gcc-C generatedatafile. c Gcc-G main. O Liu. O generatedatafile. O-o Liu -L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Rm-f *. o

Makefile comments are similar to shell, and all texts starting with "#" are comments.

The command in the Section (rule) is a common Unix Command, which can be a GCC command or any UNIX
Command

Install: Liu Chmod 750 Liu CP Liu/usr/bin   Liu: Liu. o GCC Liu. O-o Liu

Run the depend Liu summary first to generate the executable file Liu Change the generated Executable File Permission Copy the generated executable file to the appropriate installation directory.

Another example:

Clean: Rm-F *. O Delete the *. o file generated in the middle

 
Usually add a delete statement to the last link to delete the *. o file generated in the middle.

$ VI makefile Ldflags =-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu $ (ldflags) Rm-f *. o

$ Make Gcc-C main. c Gcc-C Liu. c Gcc-C generatedatafile. c Gcc-G main. O Liu. O generatedatafile. O-o Liu -L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Rm-f *. o $ Ls Comm. h Generatedatafile. c Liu. c Makefile Testm Dataf Liu Main. c Makefile. Bak Testm. c

Use the internal macro $ (RM) of make to delete the file.

VI makefile Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu $ (ldflags) $ (RM) *. o

$ Make Gcc-C main. c Gcc-C Liu. c Gcc-C generatedatafile. c Gcc-G main. O Liu. O generatedatafile. O-o Liu -L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Rm-f *. o

Replacing macro variables in the MAKEFILE file and referencing macro variables must include $ ()

$ VI makefile Ldflags =-L/usr/local/MySQL/lib/MySQL -Lmysqlclient-LZ Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu $ ldflags $ Make Gcc-C Liu. c Gcc-G main. O Liu. O generatedatafile. O-o Liu dflags GCC: dflags: no such file or Directory * ** Error code 1

$ VI makefile Liu: Main. O Liu. O generatedatafile. o Gcc-G main. O Liu. O generatedatafile. O-o Liu $ ( Ldflags) $ Make Gcc-G main. O Liu. O generatedatafile. O-o Liu-L/usr/local/MySQL/lib/MySQL-lmysqlclient -LZ

Why does make add $ () to referenced variables ()?

Because it is not a variable, it is a macro.

All file names in makefile are path names and can contain directory paths, such as src/Main. C.

Main. O: Main. c comm. h

Gcc-C main. c
$ (INC)
The source file is in the current directory.

Main. O: src/Main. c Include/COMM. h

Gcc-C src/Main. c
$ (INC)
The source file is in a subdirectory.

$ @ And $? Usage:

Target
: Depend

$ @

: $?

Liu : Main. O Liu. o Generatedatafile. o Gcc-G $? -O $ @ $ (Libs)

$?
Can replace multiple (all) depend

$ VI makefile Libs =-L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ ALL: Liu clean Liu: Main. o Liu. O generatedatafile. o Gcc-G $? -O $ @ $ (Libs) Main. O: Main. c Gcc-C $? Liu. O: Liu. c Gcc-C Liu. c Generatedatafile. O: generatedatafile. c Gcc-C $? Clean: $ (RM) *. o

No. h file is required during compilation.

$ VI makefile
Main. O: Main. c comm. h

Gcc-C main. c

The essence of the so-called "Compilation without. H" file-What Is depend used?

Description of depend: if the target check finds any new depend, recompile it.
.

<Target 1>: depend <Command 1> <Command 2>

The following depend comm. H is necessary because comm. H is a custom header file.
, May be modified

Main. O: Main. c Comm. h Gcc-C main. c

The following mysql. H is unnecessary because it is a standard header file and cannot be modified or depend.
Other standard header files, such as stdio. H, do not need to appear in depend.

Liu. O: Liu. c/usr/ /Include/MySQL. h Gcc-C Liu. c

If depend is a section, redirect it to the Section and continue to check the timestamp of depend.
 

Liu: Main. o Main. O: Main. c

If the custom header file also includes the custom header file (serial set), it should also be used in depend

Depend
Xxx. h file defects, cannot continue to use $? Now

Main. O: Main. c comm. h Gcc-C $?

$ Make Gcc-C src/Main. c Include/COMM. H-iinclude Apparently $? Compile comm. h. Now

The correct method: directly use the file name, no $? Main. O: src/Main. c Include/COMM. h Gcc-C src/Main. C $ (INC) You can only use the file name directly, not $? Now

Make with Structured Programming

• Directory tree

Mysqltmp --- SRC --- main. c Liu. c generatedatafile. c --- Include -- comm. h --- Lib -- libcomm. So or libcomm.

• In the top-level directory
  Create makefile

Call the. c file compilation in the SRC subdirectory (depend and command in the rule can both contain paths ).

VI makefile Libs =-L/usr/local/MySQL/lib/MySQL-L/export/home/MACG/mysqltmp/lib -Lmysqlclient-LZ-lcomm INC =-iinclude ALL: Liu clean Liu: Main. O Liu. O generatedatafile. o Gcc-G $? -O $ @ $ (libs) Main. O: src/ Main. c Gcc-C $? $ (INC) Custom header files cannot be repeatedly included We recommend that you include multiple files in Main. C) Or use the File Include (assuming only one file is used) Liu. O: src/ Liu. c Gcc-C $? Generatedatafile. O: src/ Generatedatafile. c Gcc-C $? Clean: $ (RM) *. o

• Make

$ Make Gcc-C src/Liu. c Gcc-C src/generatedatafile. c Gcc-G main. O Liu. O generatedatafile. O-o Liu -L/usr/local/MySQL/lib/MySQL-lmysqlclient-LZ Rm-f *. o

[MACG @ machome]:/export/home/MACG/mysqltmp> $ ls -F Makefile Dataf LIB/ Src/ Liu * Include/   [MACG @ machome]:/export/home/MACG/mysqltmp> $ ls SRC Generatedatafile. c Liu. c Main. c [MACG @ machome]:/export/home/MACG/mysqltmp> $ ls Include Comm. h [MACG @ machome]:/export/home/MACG/mysqltmp> $ ls Lib Comm. c Comm. o Libcomm. So