Thanks for the answers ! I will check reptyr out. I have looked at trying to rewrite https://github.com/jerome-pouiller/reredirect which seems to be similar to what I am looking for. I want this because I would like to write a application to catch stdout of another process for logging purposes. From the applications execution side I didn't want to make any changes. Just start the application that outputs to stdout and then start my application to capture the output. I have multiple applications that have a lot of command line flags and didn't want to have to worry about executing them threw os.exec. I thought it would be nice to be able to pass a PID and redirect any stdout to my application. After looking into it more I do understand that its a odd task haha.
On Friday, July 1, 2016 at 2:34:50 PM UTC-4, Konstantin Khomoutov wrote: > > On Fri, 1 Jul 2016 10:28:59 -0700 (PDT) > ethanl...@gmail.com <javascript:> wrote: > > > I am starting to look into intercepting a running processes output. I > > know how to do this manually by look at /proc/$PID/fd/1 or by using > > gdb etc. I do not want to use os.exec and then join the child > > processes output with the parent. I want to start Process A and > > capture the output of A in Process B. Does anyone have any advice on > > where to start or an opinion on why I should just use os.exec ? Any > > advice/help would be great ! > > I'm afraid that this would be inherently kludgy. > > As C Banning hinted, the standard output (and input) streams of a > process are _already_ connected to somewhere when a process starts up > by an operating system. They can be opened to a file or something > resembling a file -- such as an OS pipe or a socket. > > Hence what you want is "retargetting" an already opened and existing > file descriptor of a foreign process, which is not something available > in the "standard" set of system calls. > > If, for some reason, you still dearly need to do something like this, > try looking at reptyr [1] which plays dirty unportable tricks with > ptrace(). > > In any case it would be interesting to hear _why_ would you need that. > > 1. https://github.com/nelhage/reptyr > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
