stderr

问题 I have a Java GUI-based application that writes some diagnostic messages to System.out and System.err. Where are these messages output when running on Windows? (For example, on Mac OS X, they're printed to the system console log.) Edit I should add that the Java application is packaged as a .exe, so (right now) I can't launch it using java . (I can copy the individual .JAR files to the Windows test machine, I suppose.) Also, it's an app I inherited that didn't use a logging framework before;

问题 I would like to be able to redirect stderr to a C string because I need to use the string in the program I'm writing. I would like to avoid writing to a file (on the hard drive) first then readings the file to get the string. What is the best way to get this done? 回答1: You could just use setbuf() to change stderr 's buffer: #include <stdio.h> int main(void) { char buf[BUFSIZ]; setbuf(stderr, buf); fprintf(stderr, "Hello, world!\n"); printf("%s", buf); return 0; } prints: Hello, world! Hello,

问题 Hi I am trying to execute external program from Java program and read the stdout message in real time , without waiting for the program to exit. However, i found that there are different stdout behaviour in different .exe program, and I don't know how to handle it. Example 1: server1.exe is a console program. When i run it, it will continuously listening on a port. When a client is connected to it, it will generate 1 line of stdout output every 1 second. It will not exit unless i press "ctrl

问题 I need to print into a text file the lines that appear in the cmd window when the batch is running. For instance, I have the following batch script: copy D:\aaa.txt D:\bbb.txt When I launch the batch file, the cmd window displays the following lines (sorry my Windows is in french): D:\>copy D:\aaa.txt D:\bbb.txt 1 fichier(s) copié(s) I would like to automatically write these 2 lines in a text file in order to check the execution of more complex batch files and to track errors. 回答1: Redirect

问题 I am trying to intercept the red Empty page!! message that gets printed to my screen when using Tess4J . I wrote a short interceptor class that overrides print and println and replaced stdout and stderr to check for this string: private static class Interceptor extends PrintStream { public Interceptor(OutputStream out) { super(out, true); } @Override public void print(String s) { if ( !s.contains("Empty page!!") ) super.print(s); } @Override public void println(String s) { if ( !s.contains(

问题 I want to capture stderr output from my PyQt script and display it in a QMessageBox. I found these posts and tried them, but none really worked for me: Display python console messages in QMessageBox Redirecting stdout and stderr to a PyQt4 QTextEdit from a secondary thread PYQT: How to capture output of python's interpreter and display it in QEditText? I was having a couple problems. First, a single error seems to be sent as a series of separate stderr messages (at least in Python 3.4). This

问题 I have a little program, let's call it "program" by simplicity which has "normal" behaviour. It takes information from the stdin (normally typed in by the user in the keyboard) and prints out via stdout/stderr. I want to automate a process and therefore redirect stdout/stderr into "my little bash script" (which could also be another program in C/C++). It takes it as it's standard input and filters it. This means leaving out unimportant information.. and adding further information generated by

问题 I was writing a small program that had various console output strings depending upon different events. As I was looking up the best way to send these messages I came across something that was a bit confusing. I have read that stderr is used to shoot messages directly to the console - not buffered . While, in contrast, I read that stdout is buffered and is typically used to redirect messages to various streams? , that may or may not be error messages, to an output file or some other medium.

问题 I have Django web-site working on tornado and nginx. I took this tornado launcher script (tornading.py) Then I'm using python openid that outputs some information to sys.stderr. As a result I get IOError. How can I redirect it using logging package? I thought about f = open("myfile.log", "w") sys.stderr = f or python tornado.py > /dev/null 2>&1 But what is the best way to solve it? 回答1: The best way would be if the openid library didn't print to stderr, but used some kind of logging API

问题 I have a Qt/C++ acpplication which is using a C++ library. This library has a log mechanism that writes string messages to standard error. Now, I would like to be able to redirect those messages toward a panel in my Qt tool. I would like to avoid modifying the library because is adopted by many other clients. Any idea how to get at runtime these messages? Having instead the possibility of changing it what could be a good practise for carrying those messages up to the application? 回答1: That's