I have a macOS/Objective-C/Cocoa application. We want to spawn external applications, like TextEdit, to edit files created by this app. I'm creating these files by copying it into my ~/Documents directory (eventually I'd like to put it elsewhere, but I'm trying to simplify) with:
NSFileManager *defaultManager = [NSFileManager defaultManager];
[defaultManager copyItemAtPath:srcPath toPath:destPath error:&err];
NSDate *sourceModified = [self lastModificationOfFile:srcPath];
NSDictionary * attr = @{ NSFileModificationDate : sourceModified,
NSFileImmutable : [NSNumber numberWithBool:NO],
NSFilePosixPermissions : [NSNumber numberWithUnsignedLong:0666],
};
[defaultManager setAttributes:attr ofItemAtPath:destPath error:nil];
When I open this file in TextEdit, the window header says "filename.txt - Locked". Editing the document gives me the "Are you sure you want to modify the document in place?" dialog. I select "Overwrite", but then attempts to save give me "The document "filename.txt" could not be saved. You don't have permission."
However, this writes a "filename.txt.sb-a69dcdc5-7V6D2g" (or similarly named) file into my Documents directory. And files created from the bash shell with "echo blablabla > filename.txt" in that same directory open just fine.
I have tried many variations on those attributes. I cannot see any difference between the files which work and those which display "... - Locked" using "ls -la@ filename.txt" or "xattr", even side-by-side in the same directory.
Clearly I'm up against some sandboxing issue with the files I create, but all of my search results are about the other side of this problem.
