我已经卸载并安装了3次Homebrew，因为它似乎永远不会允许我安装任何东西，因为它在大多数安装结束时拒绝我的权限。
作为一个例子，我将发布我目前面临的这个libjpeg下载场景。
我尝试安装libjpeg并得到：
$ brew install libjpeg
==> Downloading https://downloads.sf.net/project/machomebrew/Bottles/jpeg-8d.mountain_lion.bottle.1.tar.gz
Already downloaded: /Library/Caches/Homebrew/jpeg-8d.mountain_lion.bottle.1.tar.gz
==> Pouring jpeg-8d.mountain_lion.bottle.1.tar.gz
Warning: Could not link jpeg. Unlinking...
Error: The brew link step did not complete successfully
The formula built, but is not symlinked into /usr/local
You can try again using `brew link jpeg'
Error: Permission denied - /usr/local/opt/jpeg
“brew链接jpeg”结果
Error: Permission denied - /usr/local/opt/jpeg
如下问题：
$ brew docto
Warning: "config" scripts exist outside your system or Homebrew directories.
./configure scripts often look for *-config scripts to determine if
software packages are installed, and what additional flags to use when
compiling and linking.
Having additional scripts in your path can confuse software installed via
Homebrew if the config script overrides a system or Homebrew provided
script of the same name. We found the following "config" scripts:
/Library/Frameworks/Python.framework/Versions/2.7/bin/python-config
/Library/Frameworks/Python.framework/Versions/2.7/bin/python2-config
/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7-config
Warning: You have unlinked kegs in your Cella
Leaving kegs unlinked can lead to build-trouble and cause brews that depend on
those kegs to fail to run properly once built. Run brew link on these:
jpeg这个权限问题已经使任何事情都不可能使用brew，我真的很感激任何的建议。
回答 3
正在寻找一个基于ajax的图像上传解决方案，我正在寻找的答案有点分散在整个这个职位。我解决的解决方案涉及FormData对象。我汇集了我放在一起的代码的基本形式。您可以看到它演示了如何使用fd.append（）将自定义字段添加到窗体，以及如何在ajax请求完成时处理响应数据。
上传html：
<!DOCTYPE html><html><head> <title>Image Upload Form</title> <script src="//code.jquery.com/jquery-1.9.1.js"></script> <script type="text/javascript"> function submitForm() { console.log("submit event"); var fd = new FormData(document.getElementById("fileinfo")); fd.append("label", "WEBUPLOAD"); $.ajax({ url: "upload.php", type: "POST", data: fd, processData: false, // tell jQuery not to process the data contentType: false // tell jQuery not to set contentType }).done(function( data ) { console.log("PHP Output:"); console.log( data ); }); return false; } </script></head><body> <form method="post" id="fileinfo" name="fileinfo" onsubmit="return submitForm();"> <label>Select a file:</label><br> <input type="file" name="file" required /> <input type="submit" value="Upload" /> </form> <div id="output"></div></body></html>如果你正在使用PHP这里是一种处理上传的方法，包括使用上面的html中演示的两个自定义字段。
upload.php的<?phpif ($_POST["label"]) { $label = $_POST["label"];}$allowedExts = array("gif", "jpeg", "jpg", "png");$temp = explode(".", $_FILES["file"]["name"]);$extension = end($temp);if ((($_FILES["file"]["type"] == "image/gif")|| ($_FILES["file"]["type"] == "image/jpeg")|| ($_FILES["file"]["type"] == "image/jpg")|| ($_FILES["file"]["type"] == "image/pjpeg")|| ($_FILES["file"]["type"] == "image/x-png")|| ($_FILES["file"]["type"] == "image/png"))&& ($_FILES["file"]["size"] < 200000)&& in_array($extension, $allowedExts)) { if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br>"; } else { $filename = $label.$_FILES["file"]["name"]; echo "Upload: " . $_FILES["file"]["name"] . "<br>"; echo "Type: " . $_FILES["file"]["type"] . "<br>"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " kB<br>"; echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br>"; if (file_exists("uploads/" . $filename)) { echo $filename . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "uploads/" . $filename); echo "Stored in: " . "uploads/" . $filename; } }} else { echo "Invalid file";}?>一个简单的上传实例：题主可以借鉴下
<script> //form Submit $("form").submit(function(evt){ evt.preventDefault(); var formData = new FormData($(this)[0]); $.ajax({ url: 'fileUpload', type: 'POST', data: formData, async: false, cache: false, contentType: false, enctype: 'multipart/form-data', processData: false, success: function (response) { alert(response); } }); return false; });</script><!--Upload Form--><form> <table> <tr> <td colspan="2">File Upload</td> </tr> <tr> <th>Select File </th> <td><input id="csv" name="csv" type="file" /></td> </tr> <tr> <td colspan="2"> <input type="submit" value="submit"/> </td> </tr> </table></form>文件上传是不是可以通过Ajax。您可以上传文件，无需使用IFrame刷新页面。你可以在这里查看更多细节
更新：
使用XHR2，支持通过AJAX上传文件。例如通过FormData对象，但不幸的是它并不是所有/旧的浏览器都支持。
FormData支持从以下桌面浏览器版本开始。IE 10+，Firefox 4.0+，Chrome 7+，Safari 5+，Opera 12+
腾讯云开发者
