Extracts the contents of a string as a NULL-terminated 8-bit string appropriate for passing to POSIX APIs.


func CFStringGetFileSystemRepresentation(_ string: CFString!, _ buffer: UnsafeMutablePointer<Int8>!, _ maxBufLen: CFIndex) -> Bool



The string to convert.


The C string buffer into which to copy the string. The buffer must be at least maxBufLen bytes in length. On return, the buffer contains the converted characters.


The maximum length of the buffer.

Return Value

true if the string is correctly converted; false if the conversion fails, or the results don’t fit into the buffer.


You can use CFStringGetMaximumSizeOfFileSystemRepresentation(_:) if you want to make sure the buffer is of sufficient length.

See Also

String File System Representations

func CFStringCreateWithFileSystemRepresentation(CFAllocator!, UnsafePointer<Int8>!) -> CFString!

Creates a CFString from a zero-terminated POSIX file system representation.

func CFStringGetMaximumSizeOfFileSystemRepresentation(CFString!) -> CFIndex

Determines the upper bound on the number of bytes required to hold the file system representation of the string.

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