Create Empty File Swift

Create empty file swift

Using your script in the linked question, try:

shell("touch file.txt")

The command touch will create the file file.txt.

You do not need the terminal for anything here, just run your .swift file and you will have your file.

In case you need the file to write to, just use something like this:

let url = URL(fileURLWithPath: "file.txt")
try "Some string".write(to: url, atomically: true, encoding: .utf8)

You file file.txt will contain the string "Some string" in it.

Update

AFAIK it is not possible to just create a file, but you could create a file with an empty string:

try "".write(to: url, atomically: true, encoding: .utf8)

As mentioned by OP in comment, it is also necessary to disable sandboxing: Remove Sandboxing

Create empty file for writing?

I don't see anything wrong with what you've got... sounds logical if you are planning on writing to the file in a stream.

If the size and availability of your data is such that you don't need to maintain an open channel to which you can stream data (which I imagine is not your case since you explicitly specified needing to create an empty file), you could eliminate the second line:

NSString *content = @"Put this in a file please.";
NSData *fileContents = [content dataUsingEncoding:NSUTF8StringEncoding];
[[NSFileManager defaultManager] createFileAtPath:@"/Some/Path/foo.txt"
                                contents:fileContents
                                attributes:nil];

How to create a file in an iOS App made with Swift?

Don't use hardcoded paths like "AppData/Documents", instead it's better to ask the system for e.g. the path to the app support directory using

let appSupportDir = try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
let filePath = appSupportDir.appendingPathComponent("points.txt").path 

create an empty file of specific size and write new data to specific position with fseek

Example:

NSString *filePath = [@"~/Desktop/FHTest.txt" stringByExpandingTildeInPath];

[[NSFileManager defaultManager] createFileAtPath:filePath contents:[NSData new] attributes:nil];
NSFileHandle *fh;

NSData *data1 = [@"test Data" dataUsingEncoding:NSUTF8StringEncoding];
fh = [NSFileHandle fileHandleForUpdatingAtPath:filePath];
[fh writeData:data1];
[fh closeFile];

NSData *data2 = [@"more Data" dataUsingEncoding:NSUTF8StringEncoding];
fh = [NSFileHandle fileHandleForUpdatingAtPath:filePath];
[fh seekToFileOffset:100];
[fh writeData:data2];
[fh closeFile];

Note that the seekToFileOffset:100 will fill expand the file as necessary filling as necessary with 0x00 bytes.

To create a file of specific size, in this case 100 bytes:

unsigned long long size = 100;
[[NSFileManager defaultManager] createFileAtPath:filePath contents:[NSData new] attributes:nil];
NSFileHandle *fh = [NSFileHandle fileHandleForUpdatingAtPath:filePath];
[fh seekToFileOffset:size-1];
[fh writeData:[@"\x00" dataUsingEncoding:NSUTF8StringEncoding]];
[fh closeFile];

New files are always empty when creating a new class in Xcode

You code shows that you created Cocoa classes not Cocoa Touch. When creating file choose iOS and then select Cocoa Touch Classes and create file sub class of UITableViewController. Then you will get as you expected.

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