You have to remember the position by calling file.tell() before the readline and then calling file.seek() to rewind. Something like: fp = open(‘myfile’) last_pos = fp.tell() line = fp.readline() while line != ”: if line == ‘SPECIAL’: fp.seek(last_pos) other_function(fp) break last_pos = fp.tell() line = fp.readline() I can’t recall if it is safe to call … Read more
If you have files that large, never use byte[] or MemoryStream in your code. Only operate on streams if you download/upload files. You have a couple of options: If you control both client and server, consider using something like tus. There are both client- and server-implementations for .NET. This would probably the easiest and most … Read more
tmpfile returns a stream-able file pointer. To get the corresponding path, ask the stream for its meta data: $file = tmpfile(); $path = stream_get_meta_data($file)[‘uri’]; // eg: /tmp/phpFx0513a The benefit of the tmpfile approach? PHP automatically removes the $path when $file goes out of scope. With tempnam, you must manually remove the created file.
Reads back to what? What is the final destination of this data? Since it sounds like you are completely IO bound, mmap and read should make no difference. The interesting part is in how you get the data to your receiver. Assuming you’re putting this data to a pipe, I recommend you just dump the … Read more
You’re going to want to close the temp file after writing to it. Just add a t.close to the end. I bet the file has buffered output.
A safe way is to use mkstemp(3).
A function like this will do it: public static bool IsFileReady(string filename) { // If the file can be opened for exclusive access it means that the file // is no longer locked by another process. try { using (FileStream inputStream = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.None)) return inputStream.Length > 0; } catch (Exception) { return … Read more
I would iterate through sample[int].xml for example and grab the next available name that is not used by a file or directory. import os i = 0 while os.path.exists(“sample%s.xml” % i): i += 1 fh = open(“sample%s.xml” % i, “w”) …. That should give you sample0.xml initially, then sample1.xml, etc. Note that the relative file … Read more
This is the correct idom (and it works fine): InputStream in = null; OutputStream out = null; try { in = new FileInputStream(inputFileName); out = new FileOutputStream(outputFileName); copy(in, out); finally { close(in); close(out); } public static void close(Closeable c) { if (c == null) return; try { c.close(); } catch (IOException e) { //log the … Read more
Atomic in general means the operation cannot be interrupted will complete or have no effect. When writing files, that is accomplished by writing to a temporary file then replacing the original with the temporary when the write completes. A crash while writing an atomic file means the original is not modified and there is a … Read more