flush

问题 Well I been doing a lot of searching on google and on here about how to flush the input stream properly. All I hear is mixed arguments about how fflush() is undefined for the input stream, and some say just do it that way, and others just say don't do it, I haven't had much luck on finding a clear efficient/proper way of doing so, that the majority of people agree on.. I am quite new at programming so I don't know all the syntax/tricks of the language yet, so my question which way is the most

问题 Can someone explain the concept of buffers a bit more explicitly? I understand that buffers are data structures where characters are stored, and the place where the data is to be read from. What is the idea of flushing buffers? When a buffer is flushed, is this referring to the act of writing the characters stored in it? From the text: To avoid the overhead of writing in response to each output request, the library uses the buffer to accumulate the characters to be written, and flushes the

问题 I have a question in my mind that, while writing into the file, before closing is done, should we include flush()??. If so what it will do exactly? dont streams auto flush?? EDIT: So flush what it actually do? 回答1: Writers and streams usually buffer some of your output data in memory and try to write it in bigger blocks at a time. flushing will cause an immediate write to disk from the buffer, so if the program crashes that data won't be lost. Of course there's no guarantee, as the disk may

问题 I have a question in my mind that, while writing into the file, before closing is done, should we include flush()??. If so what it will do exactly? dont streams auto flush?? EDIT: So flush what it actually do? 回答1: Writers and streams usually buffer some of your output data in memory and try to write it in bigger blocks at a time. flushing will cause an immediate write to disk from the buffer, so if the program crashes that data won't be lost. Of course there's no guarantee, as the disk may

问题 <?php for($i=0;$i<20;$i++) { echo 'printing...<br />'; ob_flush(); flush(); usleep(300000); } ?> Url that contains the code: http://domainsoutlook.com/sandbox/delayed.php I have a dedicated server so I can make the changes. I am running apache and nginx as the proxy server. 回答1: You're using ob_flush without ob_start , so there is nothing to flush for it. It also depends on the webserver and proxy and its settings. You should disable buffering for Nginx (add "proxy_buffering off;" to the

问题 I am learning C++ and I found something that I can't understand: Output buffers can be explicitly flushed to force the buffer to be written. By default, reading cin flushes cout ; cout is also flushed when the program ends normally. So flushing the buffer (for example an output buffer): does this clear the buffer by deleting everything in it or does it clear the buffer by outputting everything in it? Or does flushing the buffer mean something completely different? 回答1: Consider writing to a

问题 I am learning C++ and I found something that I can't understand: Output buffers can be explicitly flushed to force the buffer to be written. By default, reading cin flushes cout ; cout is also flushed when the program ends normally. So flushing the buffer (for example an output buffer): does this clear the buffer by deleting everything in it or does it clear the buffer by outputting everything in it? Or does flushing the buffer mean something completely different? 回答1: Consider writing to a

问题 What's the difference between ob_flush() and flush() and why must I call both? The ob_flush() reference says: This function will send the contents of the output buffer (if any). The flush() reference says: Flushes the write buffers of PHP and whatever backend PHP is using (CGI, a web server, etc). However, it continues to say: [it] may not be able to override the buffering scheme of your web server… So, seems to me that I could just use ob_flush() all of the time. However, I get strange

问题 If I want to receive a one character input in C, how would I check to see if extra characters were sent, and if so, how would I clear that? Is there a function which acts like getc(stdin), but which doesn't prompt the user to enter a character, so I can just put while(getc(stdin)!=EOF); ? Or a function to peek at the next character in the buffer, and if it doesn't return NULL (or whatever would be there), I could call a(nother) function which flushes stdin? Edit So right now, scanf seems to

问题 I'm on Ubuntu. When I run ghci on Terminal and do this: Prelude Control.Monad System.IO> forever $ getChar >>= print The result is something like this: a'a' b'b' C'C' %'%' \'\\' 1'1' ''\'' "'"' ^X'\CAN' ^?'\DEL' ^CInterrupted. That is, the characters I type in my keyboard are being flushed into output. How can I prevent this and have only print as the writer? 回答1: To prevent input being flushed into the output (or "echoed"), use hSetEcho stdin False. Prelude> import System.IO Prelude System