read-write

Writing to stdin and reading from stdout (UNIX/LINUX/C Programming)

╄→尐↘猪︶ㄣ 提交于 2019-11-26 08:27:53
问题 I was working on an assignment where a program took a file descriptor as an argument (generally from the parent in an exec call) and read from a file and wrote to a file descriptor, and in my testing, I realized that the program would work from the command-line and not give an error if I used 0, 1 or 2 as the file descriptor. That made sense to me except that I could write to stdin and have it show on the screen. Is there an explanation for this? I always thought there was some protection on

Adding items to Swift array across multiple threads causing issues (because arrays aren't thread safe) - how do I get around that?

天大地大妈咪最大 提交于 2019-11-26 08:26:06
问题 I want to add given blocks to an array, and then run all the blocks contained in the array, when requested. I have code similar to this: class MyArrayBlockClass { private var blocksArray: Array<() -> Void> = Array() private let blocksQueue: NSOperationQueue() func addBlockToArray(block: () -> Void) { self.blocksArray.append(block) } func runBlocksInArray() { for block in self.blocksArray { let operation = NSBlockOperation(block: block) self.blocksQueue.addOperation(operation) } self

How to read/write arbitrary bits in C/C++

蓝咒 提交于 2019-11-26 04:36:34
问题 Assuming I have a byte b with the binary value of 11111111 How do I for example read a 3 bit integer value starting at the second bit or write a four bit integer value starting at the fifth bit? 回答1: Some 2+ years after I asked this question I'd like to explain it the way I'd want it explained back when I was still a complete newb and would be most beneficial to people who want to understand the process. First of all, forget the "11111111" example value, which is not really all that suited

Create thread safe array in Swift

这一生的挚爱 提交于 2019-11-26 02:17:32
问题 I have a threading problem in Swift. I have an array with some objects in it. Over a delegate the class gets new objects about every second. After that I have to check if the objects are already in the array, so I have to update the object, otherwise I have to delete / add the new object. If I add a new object I have to fetch some data over the network first. This is handelt via a block. Now my problem is, how to I synchronic this tasks? I have tried a dispatch_semaphore, but this one blocks

Reading/Writing a MS Word file in PHP

て烟熏妆下的殇ゞ 提交于 2019-11-25 23:37:35
问题 Is it possible to read and write Word (2003 and 2007) files in PHP without using a COM object? I know that I can: $file = fopen(\'c:\\file.doc\', \'w+\'); fwrite($file, $text); fclose(); but Word will read it as an HTML file not a native .doc file. 回答1: Reading binary Word documents would involve creating a parser according to the published file format specifications for the DOC format. I think this is no real feasible solution. You could use the Microsoft Office XML formats for reading and