stderr

The Problem I've been trying to write a program that logs uncaught exceptions and syntax errors for a subprocess. Easy, right? Just pipe stderr to the right place. However , the subprocess is another python program- I'll call it test.py - that needs to run as if its output/errors are not being captured. That is, running the logger program needs to seem like the user has just run python test.py as normal. Further complicating the issue is the problem that raw_input actually gets sent to stderr if readline is not used. Unfortunately, I can't just import readline , since I don't have control over

Is there a way to tell curl to output errors to stderr, and everything else to stdout? The reason is that I am using curl from the command line (actually a cronjob) to upload a file to an FTP site every evening. Unfortunately because curl outputs status information on stderr, I receive an e-mail about an error when nothing actually went wrong. (I'm redirecting stdout to a log file, but leaving stderr unchanged so that cron will e-mail it to me if there is any output.) There are options to make curl silent, or output everything to stdout, however both these alternatives prevent errors from

服务端： #!/usr/bin/env python# -*- coding: utf-8 -*-import socketimport subprocessimport structimport jsonphone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)phone.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR,1) # 端口复用phone.bind(('127.0.0.1', 8090))phone.listen(10)while True: # 连接循环 connt , client = phone.accept() print('starting ....') print(client) while True: # 通信循环 try: # 1.收到命令： cmd = connt.recv(1024) if not cmd :continue # 适用于Linux 操作系统 # 2.执行命令： ojb = subprocess.Popen(cmd.decode('utf-8'),shell=True,stdout=subprocess.PIPE,stderr=subprocess.PIPE) stdout = ojb.stdout.read() stderr =

I want to redirect the stderr output of a subprocess to stdout. The constant STDOUT should do that, shouldn't it? However, $ python >/dev/null -c 'import subprocess;\ subprocess.call(["ls", "/404"],stderr=subprocess.STDOUT)' does output something. Why is that the case, and how do I get the error message on stdout? A close read of the source code gives the answer. In particular, the documentation is misleading when it says: subprocess.STDOUT Special value that (...) indicates that standard error should go into the same handle as standard output. Since stdout is set to "default" ( -1 ,

After searching around for a reason that qDebug() statements work fine with Qt's standard message handler but fail when I switch to my own, I'm appealing here to see if anyone else has any experience with the problem. Things I know about / have tried, that do nothing... 1) CONFIG += console 2) DEFINES -= QT_NO_WARNING_OUTPUT QT_NO_DEBUG_OUTPUT 3) ::fprintf(stderr, "ERROR\n"); ::fflush(stderr); 4) ::fprintf(stdout, "OUTPUT\n"); ::fflush(stdout); 5) std::cerr << "CERROR" << std::endl; std::cerr.flush(); However it works correctly when using the built in handler (ie it prints the message to the

I have a Perl script which forks and daemonizes itself. It's run by cron, so in order to not leave a zombie around, I shut down STDIN,STDOUT, and STDERR: open STDIN, '/dev/null' or die "Can't read /dev/null: $!"; open STDOUT, '>>/dev/null' or die "Can't write to /dev/null: $!"; open STDERR, '>>/dev/null' or die "Can't write to /dev/null: $!"; if (!fork()) { do_some_fork_stuff(); } The question I have is: I'd like to restore at least STDOUT after this point (it would be nice to restore the other 2). But what magic symbols do I need to use to re-open STDOUT as what STDOUT used to be? I know that

NB. I have seen Log output of multiprocessing.Process - unfortunately, it doesn't answer this question. I am creating a child process (on windows) via multiprocessing. I want all of the child process's stdout and stderr output to be redirected to a log file, rather than appearing at the console. The only suggestion I have seen is for the child process to set sys.stdout to a file. However, this does not effectively redirect all stdout output, due to the behaviour of stdout redirection on Windows. To illustrate the problem, build a Windows DLL with the following code #include <iostream> extern