On Unix systems you can do the following: import sys import select if select.select([sys.stdin, ], [], [], 0.0)[0]: print(“Have data!”) else: print(“No data”) On Windows the select module may only be used with sockets though so you’d need to use an alternative mechanism.
Runtime.getRuntime().addShutdownHook(new Thread() { public void run() { /* my shutdown code here */ } }); This should be able to intercept the signal, but only as an intermediate step before the JVM completely shutdowns itself, so it may not be what you are looking after. You need to use a SignalHandler (sun.misc.SignalHandler) to intercept the … Read more
I’ve had some success in solving this problem of mine. Here are the details, with some explanations, in case anyone having a similar problem finds this page. But if you don’t care for details, here’s the short answer: Use PTY.spawn in the following manner (with your own command of course): require ‘pty’ cmd = “blender … Read more
You can’t hook a file directly to stdin, but you can still access stdin. Get-Content input.txt | ./program > output.txt
http://golang.org/pkg/fmt/#Scanf All the included libraries in Go are well documented. That being said, I believe func main() { var i int _, err := fmt.Scanf(“%d”, &i) } does the trick
It might be better to use communicate: from subprocess import Popen, PIPE, STDOUT p = Popen([‘myapp’], stdout=PIPE, stdin=PIPE, stderr=PIPE) stdout_data = p.communicate(input=”data_to_write”)[0] “Better”, because of this warning: Use communicate() rather than .stdin.write, .stdout.read or .stderr.read to avoid deadlocks due to any of the other OS pipe buffers filling up and blocking the child process.
Simple: this is undefined behavior, since fflush is meant to be called on an output stream. This is an excerpt from the C standard: int fflush(FILE *ostream); ostream points to an output stream or an update stream in which the most recent operation was not input, the fflush function causes any unwritten data for that … Read more
The correct notation for Process Substitution is: while read i; do echo $i; done < <(echo “$FILECONTENT”) The last value of i assigned in the loop is then available when the loop terminates. An alternative is: echo $FILECONTENT | { while read i; do echo $i; done …do other things using $i here… } The … Read more
You need dynamic memory management, and use the fgets function to read your line. However, there seems to be no way to see how many characters it read. So you use fgetc: char * getline(void) { char * line = malloc(100), * linep = line; size_t lenmax = 100, len = lenmax; int c; if(line … Read more
Use isatty: #include <stdio.h> #include <io.h> … if (isatty(fileno(stdin))) printf( “stdin is a terminal\n” ); else printf( “stdin is a file or a pipe\n”); (On windows they’re prefixed with underscores: _isatty, _fileno)