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    <p>Your solution is correct, though Apple includes an important note within <code>NSFileManager.h</code>:</p> <pre><code>/* The following methods are of limited utility. Attempting to predicate behavior based on the current state of the filesystem or a particular file on the filesystem is encouraging odd behavior in the face of filesystem race conditions. It's far better to attempt an operation (like loading a file or creating a directory) and handle the error gracefully than it is to try to figure out ahead of time whether the operation will succeed. */ - (BOOL)fileExistsAtPath:(NSString *)path; - (BOOL)fileExistsAtPath:(NSString *)path isDirectory:(BOOL *)isDirectory; - (BOOL)isReadableFileAtPath:(NSString *)path; - (BOOL)isWritableFileAtPath:(NSString *)path; - (BOOL)isExecutableFileAtPath:(NSString *)path; - (BOOL)isDeletableFileAtPath:(NSString *)path; </code></pre> <p>Essentially, if multiple threads/processes are modifying the file system simultaneously the state could change in between calling <code>fileExistsAtPath:isDirectory:</code> and calling <code>createDirectoryAtPath:withIntermediateDirectories:</code>, so it is superfluous and possibly dangerous to call <code>fileExistsAtPath:isDirectory:</code> in this context.</p> <p>For your needs and within the limited scope of your question it likely would not be a problem, but the following solution is both simpler and offers less of a chance of future issues arising:</p> <pre><code>NSFileManager *fileManager= [NSFileManager defaultManager]; NSError *error = nil; if(![fileManager createDirectoryAtPath:directory withIntermediateDirectories:YES attributes:nil error:&amp;error]) { // An error has occurred, do something to handle it NSLog(@"Failed to create directory \"%@\". Error: %@", directory, error); } </code></pre> <p>Also note from <a href="http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSFileManager_Class/Reference/Reference.html%23//apple_ref/doc/uid/20000305-SW5" rel="noreferrer">Apple's documentation</a>:</p> <blockquote> <p><strong>Return Value</strong></p> <p>YES if the directory was created, YES if createIntermediates is set and the directory already exists), or NO if an error occurred.</p> </blockquote> <p>So, setting <code>createIntermediates</code> to <code>YES</code>, which you already do, is a de facto check of whether the directory already exists.</p>
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