Make 命令

1. make 輔助說明

   [dywang@dyw219 make1]$ make --help
   Usage: make [options] [target] ...
   Options:
     -b, -m                      Ignored for compatibility.
     -B, --always-make           Unconditionally make all targets.
     -C DIRECTORY, --directory=DIRECTORY
                                 Change to DIRECTORY before doing anything.
     -d                          Print lots of debugging information.
     --debug[=FLAGS]             Print various types of debugging information.
     -e, --environment-overrides
                                 Environment variables override makefiles.
     -f FILE, --file=FILE, --makefile=FILE
                                 Read FILE as a makefile.
     -h, --help                  Print this message and exit.
     -i, --ignore-errors         Ignore errors from commands.
     -I DIRECTORY, --include-dir=DIRECTORY
                                 Search DIRECTORY for included makefiles.
     -j [N], --jobs[=N]          Allow N jobs at once; infinite jobs with no arg.
     -k, --keep-going            Keep going when some targets can't be made.
     -l [N], --load-average[=N], --max-load[=N]
                                 Don't start multiple jobs unless load is below N.
     -L, --check-symlink-times   Use the latest mtime between symlinks and target.
     -n, --just-print, --dry-run, --recon
                                 Don't actually run any commands; just print them.
     -o FILE, --old-file=FILE, --assume-old=FILE
                                 Consider FILE to be very old and don't remake it.
     -p, --print-data-base       Print make's internal database.
     -q, --question              Run no commands; exit status says if up to date.
     -r, --no-builtin-rules      Disable the built-in implicit rules.
     -R, --no-builtin-variables  Disable the built-in variable settings.
     -s, --silent, --quiet       Don't echo commands.
     -S, --no-keep-going, --stop
                                 Turns off -k.
     -t, --touch                 Touch targets instead of remaking them.
     -v, --version               Print the version number of make and exit.
     -w, --print-directory       Print the current directory.
     --no-print-directory        Turn off -w, even if it was turned on implicitly.
     -W FILE, --what-if=FILE, --new-file=FILE, --assume-new=FILE
                                 Consider FILE to be infinitely new.
     --warn-undefined-variables  Warn when an undefined variable is referenced.
   
   This program built for x86_64-redhat-linux-gnu
   Report bugs to <bug-make@gnu.org>
   

2. make 常用的選項及參數：
   1. -j N：讓 make 在同一個時間執行 N 個命令，以加速編譯的時間。
   2. -k：讓 make 在遇到錯誤時，仍然繼續運行，不停止在第一個問題點。
   3. -n：告訴 make 只印出將會進行的工作，而不真正去編譯。
   4. -f <filename>：告訴 make 該使用的 makefile 檔案。如果不使用這個選項， make 會依序尋找目錄中的 GNUmakefile, makefile, Makefile。