directing output from executed process to current cmd - windows

Can I execute a program from a JScript script in such a way that the out put of the executed program will be written to the current console?
Currently I am using Shell.Application.ShellExecute and it is opening another new console for the executed application.
The JScript in my case is a wrapper around a compiler which is executed with the ShellExecute. So what happens is that all the compiler errors are lost because they are printed in another console.

If all you are worried about is capturing your compiler output then you can redirect the output to a file (I suggest both stdout and stderr). Something like this:
var shell = new ActiveXObject("WScript.Shell");
shell.Exec('YourCommand 1>yourOutput.txt 2>&1 ')
If you really want to see the ouptut in your current console window (I don't blame you), then you can use this:
var shell = new ActiveXObject("WScript.Shell");
WScript.StdOut.Write( shell.Exec('YourCommand 2>&1').StdOut.ReadAll() );
Note - if your command has the potential for asking for input, then you must provide input via a pipe or redirection in the command string (or you could redirect input to nul). Otherwise the program will hang.

Related

Why can't I redirect stdout/err of a program run by a batch file, called by another batch?

If I have this batch:
ScriptA.bat
someprog.exe
And this one:
ScriptB.bat
CALL ScriptA.bat
And I execute a command like:
ScriptB.bat > test.log
The output from someprog.exe is not logged. It flows through to the console. How can I avoid having to explicitly pipe the output of someprog.exe to a file, and instead just capture that from a higher level?
(Note I ultimately want to do this with a great many scripts launching assorted exes from inside those nesting, and I can't edit them all to redirect the output of each and every sub process they invoke).
I found the answer to this on another SO thread:
https://stackoverflow.com/a/11955380/3220983
As you'll see if reading the comments under the question, the problem I was encountering was that the messages I couldn't capture were not being piped to stdout or stderr at all! They were going straight to the console via something akin to a CON redirect from inside the specific executable I was trying to use.
The link I posted shows how to launch a PowerShell script from a batch script, which captures the entire console window contents, inclusive of CON output!

Is it possible to obtain the _raw_/_unprocessed_ command line?

The windows API provides GetCommandLine() which returns the cooked command line used to start a process.
For instance, if a console application is started with the command:
MyProg.exe > OutputHere
The command line seen by MyProg.exe will not include the portion
> OutputHere
I'd like to somehow get the command line exactly as it was. Is this possible ? and if yes, how ?
Suggestions in C and/or plain (no objects) Delphi greatly appreciated. Creative solutions welcome (hopefully, not requiring ring 0 code.)
Thank you very much for your help.
NOTE: I can tell if the input/output, etc has been redirected but, that is not what I'm looking for. I need the original/uncooked command line.
The redirection or piping of stdin, stdout and stderr is handled the command interpreter, typically cmd.exe. The interpreter parses the command and creates the necessary files and pipes, and then creates the one or more processes needed to implement your command.
The processes that are created have no knowledge of the original command, they only get that part of the command that is not related to piping and redirection.
So what you are trying to do is not possible, at least within your process. The only thing that knows the original command is the command interpreter.
Whether or not you can retrieve the full command line including the pipe commands depends on whether your start the program in a command window or for example using the "Run" command from the Start menu. If you use the "Run" command from the Start menu GetCommandLine actually retrieves the full command line including the redirection commands, but redirection does not work as it seems to be a feature of CMD.EXE.
As others have pointed out, what are you trying to achieve here / why do you need to capture the redirection commands?

Is it possible to capture output from a system command and redirect it?

What I would like to do is:
run a ruby script...
that executes a shell command
and redirects it to a named pipe accessible outside the script
from the system shell, read from that pipe
That is, have the Ruby script capture some command output and redirect it in such a way that it's connectable to from outside the script?
I want to mention that the script cannot simply start and exit, since it's a REPL. The idea is that using the REPL you would be able to run a command and redirect its output elsewhere to consume it.
Using abort and an exit message, will pass the message to STDERR (and the script will fail with exit code 1). You can pass this shell command output in this way.
This is possibly not the only (or best) way, but it has worked for me in the past.
[edit]
You can also redirect the output to a file (using standard methods), and read that file outside the ruby script.
require 'open3'
stdin, stderr, status = Open3.capture3(commandline)
stdin.chomp #Here, you should ge
Incase, if someone wanted to use you can get the output via stdin.chomp

Ruby Command Prompt Commands

I am designing a ruby program that needs to run a command and store it a variable.
var = exec('some command');
This doesn't work the way I want it to, it just prints the output from the command prompt and then ends the program.
So is there a function that doesn't end the program, doesn't print the cmd output and stores the information in a variable?
Thanks in advance.
You need to use either Ruby's built in backtick syntax, or use %x
output = `some command`
or
output = %x(some "command")
Open3 grants you access to stdin, stdout, stderr and a thread to wait
the child process when running another program. You can specify
various attributes, redirections, current directory, etc., of the
program as Process.spawn.
See the various ways of executing a command

Is there any way to redirect stderr output from a command run with “start” in the Windows command line?

I have a program that I want to automate runs for, since it takes awhile to complete. For some reason it outputs everything to stderr instead of stdout, and I'd like to check on its progress, so I find myself needing to redirect stderr output within a start command.
I tried this:
start "My_Program" "C:\Users\Me\my_program.exe" --some --presets --for --my_program.exe --output "C:\Users\Me\output_file_for_my_program" "C:\Users\Me\input_file_for_my_program" 2>"C:\Users\Me\my_program_output.log"
But it turns out that the redirect is being picked up by start, so that I get a 0-byte file with the result of "start" - namely, nothing. Is there any way to make the output redirection attach in some way to the output of my_program?
I've experimented with escaping, and neither "^2>" nor "2^>" seem to work.
If "Workaround Oriented Programmming" is acceptable (it probably is, you are programming Windows Batch lol), you could put the problematic code line in another .BAT file, without any "start" and then "start" this other BAT.

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