Macos 使用自制程序安装optipng：未找到命令（rbenv？）

我已成功安装optipng：

  $ brew install optipng
  ==> Downloading https://downloads.sourceforge.net/project/optipng/OptiPNG/optipng-0.7.5/optipng-0.7.5.tar.gz
  Already downloaded: /Library/Caches/Homebrew/optipng-0.7.5.tar.gz
  ==> Patching
  patching file src/optipng/osys.c
  ==> ./configure --with-system-zlib --prefix=/usr/local/Cellar/optipng/0.7.5 --mandir=/usr/local/Cellar/optipng/0.7.5/share/man
  ==> make install
  Ok i found out that I had the 
image_optim_bin
 gem in one of my projects installed, after uninstalling this gem for all ruby versions, the command finally works!


$ gem uninstall image_optim_bin
Remove executables:
  advdef, advmng, advpng, advzip, jpegoptim, jpegtran, optipng, pngcrush, pngout

in addition to the gem? [Yn]  
Removing advdef
Removing advmng
Removing advpng
Removing advzip
Removing jpegoptim
Removing jpegtran
Removing optipng
Removing pngcrush
Removing pngout
Successfully uninstalled image_optim_bin-0.0.4 

$brew安装选项PNG
==>下载https://downloads.sourceforge.net/project/optipng/OptiPNG/optipng-0.7.5/optipng-0.7.5.tar.gz
已下载：/Library/Caches/Homebrew/optipng-0.7.5.tar.gz
==>修补
修补文件src/optipng/osys.c
==>。/configure--with-system-zlib--prefix=/usr/local/ceral/optipng/0.7.5--mandir=/usr/local/ceral/optipng/0.7.5/share/man
==>进行安装
好的，我发现我在我的一个项目中安装了
image\u optim\u bin
gem，在为所有ruby版本卸载这个gem之后，这个命令终于起作用了

$ optipng
Synopsis:
    optipng [options] files ...
Files:
    Image files of type: PNG, BMP, GIF, PNM or TIFF
Basic options:
    -?, -h, -help show the extended help
    -o <level>    optimization level (0-7)    [default: 2]
    -v      run in verbose mode / show copyright and version info

打开新的终端，现在可以工作了：

$optipng
简介：
optpng[options]文件。。。
文件夹：
类型为PNG、BMP、GIF、PNM或TIFF的图像文件
基本选择：
-？，-h，-help显示扩展的帮助
-o优化级别（0-7）[默认值：2]
-v在详细模式下运行/显示版权和版本信息