I have a problem with reading input directly at the start of the program – I would like to start a program like:
program.exe file.txt
so my program.exe will start and find, that it should load file.txt and do something with it (code for doing something I already have)..
Writing:
read(FileName);
on the first line of my main program is not working – the program is still waiting for input after the start.
This is, what I actually wanted to do: http://wiki.freepascal.org/Command_line_parameters_and_environment_variables
So for input:
program.exe file.txt
the program, which resolve which file I should open will be:
program FindGivenFileName;
{$mode objfpc}{$H+}
var FileName: string;
begin
FileName := ParamStr(1);
{next parts of code are missing here, but working}
end.
In the array of ParamStr, 0 is name of the program and numbers higher are paramaters – the first parameter is ParamStr(1), second is ParamStr(2) and so on.
You can always redirect input from file to your console application by running it with:
program.exe < file.txt
in the console (will work in both Linux and Windows).
Related
I am trying to prompt the user of my .jl file to enter user entered multiple destinations.
Basically I need the user to give an input & an output. I know in java you would use a scanner, or accept arguments when it is compiled in the command line. I am fine with either option. From what I have found looking through the Julia Documentation I think I could accomplish the first way of assigning a variable to the readline function.
(String)in = (String)Readline(STDIN)
From my understanding the variable 'in' should now contain a String of the user's input. I am encountering an error, in that when I compile my .jl code, because my command prompt does not stop to read user input, and just finishes reading the .jl code.
The first item to note in the code in your question is:
(String)in = (String)Readline(STDIN)
Julia 1.0.0 now uses stdin instead of STDIN.
Next, the (String) typecasting is not something you need or want to do in Julia.
Thus your code could read (though we get an error):
julia> in = readline(stdin)
This is a test.
ERROR: cannot assign variable Base.in from module Main
So variable in is in conflict with a Julia Base.in variable. Just use a another variable name.
julia> response = readline(stdin)
This is a test.
"This is a test"
This code is now working, but it has no prompt. Your answer provides an example input function with a prompt which you defined like this:
julia> function input(prompt::AbstractString="")
print(prompt)
return chomp(readline())
end
input (generic function with 2 methods)
The chomp function removes a single trailing \n newline character from the input string. Docs here.
Example use of the function here:
julia> input_file = input("Please enter input file name: ")
Please enter input file name: Data.txt
"Data.txt"
julia> output_file = input("Please enter output file name: ")
Please enter output file name: Output.txt
"Output.txt"
Command Line Args Method
As the docs point out, to just print out the arguments given to a script, you can do something like this:
println("Arguments passed to ", PROGRAM_FILE, ":")
for arg in ARGS
println(arg)
end
Here is an example of above code running on the Windows command line:
c:\OS_Prompt>julia PrintArgs.jl Data.txt Output1.txt Output2.txt Output3.txt
Arguments passed to PrintArgs.jl:
Data.txt
Output1.txt
Output2.txt
Output3.txt
You can also print out the script file name as shown, PrintArgs.jl.
After searching & testing I found one solution and decided to reply to it here. I had to declare my own function to be able to get the program to accept user input.
function input(prompt::AbstractString="")
print(prompt)
return chomp(readline())
end
I am not sure what the chomp function does, but I know it works for what I was asking. I am still curious if you can do something in Julia similar to java and C String args[], in which you pass extra information while you are telling your command to run. Something like the following.
Julia testFile.jl goHere.txt lookHere.txt
I have a console app (Visual Studio - VB), it runs, it does it's job.
I also have a batch file that runs the program and everything, but I want the output of my console app to also send to a text file.
This is my current batch, which creates the text file, but nothing is in it.
Start "" "C:\Users\wrossi\Desktop\NetLogOnSysInfo Solution\NetLogOnSysInfo Project\bin\Debug\NetLogOnSysInfo Project.exe" -all >>%ComputerName%.txt
Exit
Not sure if the batch is wrong, or if I should look at my program. Also, how do I define a path so I can put the output file exactly where I want it?
"C:\Users\wrossi\Desktop\
NetLogOnSysInfo Solution\NetLogOnSysInfo Project\bin\Debug\NetLogOnSysInfo Project.exe"
-all > %ComputerName%.txt
No need to use Start.
You are pretty close to what I think you want to do:
c:\console.exe > c:\output.exe
c:\console.exe or wherever the location of your console app > redirect stdout (use >> to append) c:\output.txt or wherever you want to create the text file.
Hope this helped.
Also just in case:
type stdin.txt | console.exe > stdout.txt
In the above example you can redirect an input from stdin.txt and pipe it into console.exe then redirect the output of console.exe to stdout.txt
I found one code recently after searching alot
if u wanna run .bat file in vb or c# or simply
just add this in the same manner in which i have written
here is the code
code > C:\Users\Lenovo\Desktop\output.txt
just replace word "code" with your .bat file code or command and after that the directory of output file
I workin' with Torch7 and Lua programming languages. I need a command that redirects the output of my console to a file, instead of printing it into my shell.
For example, in Linux, when you type:
$ ls > dir.txt
The system will print the output of the command "ls" to the file dir.txt, instead of printing it to the default output console.
I need a similar command for Lua. Does anyone know it?
[EDIT] An user suggests to me that this operation is called piping. So, the question should be: "How to make piping in Lua?"
[EDIT2] I would use this # command to do:
$ torch 'my_program' # printed_output.txt
Have a look here -> http://www.lua.org/pil/21.1.html
io.write seems to be what you are looking for.
Lua has no default function to create a file from the console output.
If your applications logs its output -which you're probably trying to do-, it will only be possible to do this by modifying the Lua C++ source code.
If your internal system has access to the output of the console, you could do something similar to this (and set it on a timer, so it runs every 25ms or so):
dumpoutput = function()
local file = io.write([path to file dump here], "w+")
for i, line in ipairs ([console output function]) do
file:write("\n"..line);
end
end
Note that the console output function has to store the output of the console in a table.
To clear the console at the end, just do os.execute( "cls" ).
I am trying a bit of experiments with airmon-ng script in Linux. Meanwhile i want to redirect output of a process "airodump-ng mon0" to a file. I can see the instantaneous output on the screen. The feature of this process is that it won't stop execution(actually it is a script to scan for AP and clients, it will keep on scanning) unless we use ctrl+c.
Whenever i try
airodump-ng mon0 > file.txt
i won't get the output in the file.
My primary assumption is that the shell will write it to the file only after completing the execution. But in the above case i stopped the execution(as the execution won't complete).
So to generalize i can't pipe the output of a running process to a file. How can i do that?
Or is there any alternative way to stop the execution of the process(for example after 5 seconds) and redirect the current output to a file?
A process may send output to standard output or standard error to get it to the terminal. Generally, the former is for information and the latter for errors, but in some cases, a process may mix them up.
I'm supposing that in your case, the standard error is being used. To get both of these to the output file, you can use:
airmon-ng mon0 > file.txt 2>&1
This says to send standard output to file.txt and to reroute 2 (which is the file id for standard error) into 1 (the file id for standard output) so that it also goes to the file.
I'm trying to implement a simple terminal GUI using bash's interactive mode. I successfully invoked bash, get its stdout and print everything to a text view. I forward the user input from the text view to bash's stdin, to be able to run commands. It works great, except I don't get any error messages.
However, when I proceeded to print bash's stderr to my text view, I noticed something strange. In addition to now receiving error messages, bash seems to pass everything from stdin to stderr. Because of this, every character I type is printed twice (once normally because I enter it, and once because I print everything from stderr).
It also seems to print the prompt via stderr (bash-3.2$). Is this the expected behavior? Can this be suppressed?
I also tried to just capture use input (and not let the user type directly into the text view) and rely on bash to print the user input. This is almost working, except the order of the output via stdout and stderr is random:
If I type a command like echo test and hit enter, sometimes I get this:
(the second test is the output, I didn't type testtest)
bash-3.2$ echo testtest
bash-3.2$
Sometimes I get:
bash-3.2$ echo test
bash-3.2$ test
The order in which I receive the final \n, the output and the next bash-3.2$ is obviously mixed up.
There is no way to read stdout and stderr in the "correct" order, because there is no notion of order between different pipes. But you can ensure that both are sent to the same pipe (i.e. same file descriptor) instead of having each one go to a separate pipe. To do that, look on the options of whatever you use to start the bash subprocess; or maybe start a command line like bash -c 'bash 2>&1'.