command-line-arguments

问题 I need to sort n number of strings lexicographically that are arguments of a function with variable number of arguments. In main function, strings are read as command line arguments. Here is my code: #include <stdio.h> #include <stdlib.h> #include <stdarg.h> #include <string.h> void sort(int n,...) { //store optional arguments (strings) to array arr va_list args; va_start(args,n); char **arr=malloc(n * sizeof(char*)); int i; for(i=0;i<n;i++) arr[i]=malloc((strlen(va_arg(args,char*)) + 1) *

问题 I am trying to run this command in windows: ping -n 5 127.0.0.1 > nul I get the error: 'ping' is not recognized as an internal or external command operable program or batch fie. Why can't windows find ping? Here is my script where it does not work: @ECHO OFF ::set path SET path=M:\\5.bmp :findfile IF EXIST %path% ( ECHO File found ) ELSE ( ECHO File not found ping -n 5 127.0.0.1 > nul goto findfile ) 回答1: You have overridden the PATH environment variable, so the command processor can no

问题 I'm currently going through Learn Python The Hard Way. I think this example might be out dated so I wanted to get feedback here on it. I'm using Python 3.1 from sys import argv script, first, second, third = argv print("the script is called:", (script)) print("your first variable is:", (first)) print("your second variable is:", (second)) print("your third variable is:", (third)) I'm getting this error: Traceback (most recent call last): File "/path/ch13.py", line 3, in <module> script, first,

问题 I'm currently going through Learn Python The Hard Way. I think this example might be out dated so I wanted to get feedback here on it. I'm using Python 3.1 from sys import argv script, first, second, third = argv print("the script is called:", (script)) print("your first variable is:", (first)) print("your second variable is:", (second)) print("your third variable is:", (third)) I'm getting this error: Traceback (most recent call last): File "/path/ch13.py", line 3, in <module> script, first,

问题 I'm using argparse in python to parse commandline arguments: parser = ArgumentParser() parser.add_argument("--a") parser.add_argument("--b") parser.add_argument("--c") args = parser.parse_args() Now I want to do some calculations with a , b , and c . However, I find it tiresome to write args.a + args.b + args.c all the time. Therefore, I'm extracting those variables: a, b, c = [args.a, args.b, args.c] Such that I can write a + b + c . Is there a more elegant way of doing that? Manual

问题 This is my script def main(argv): if len(sys.argv)>1: for x in sys.argv: build(x) if __name__ == "__main__": main(sys.argv) so from the command line I write python myscript.py commandlineargument I want it to skip myscript.py and simply run commandlineargument through commandlineargument(n) so I understand that my for loop doesn't account for this, but how do I make it do that? 回答1: Since sys.argv is a list, you can use slicing sys.argv[1:] : def main(argv): for x in argv[1:]: build(x) if _

问题 All my scripts use Unicode literals throughout, with from __future__ import unicode_literals but this creates a problem when there is the potential for functions being called with bytestrings, and I'm wondering what the best approach is for handling this and producing clear helpful errors. I gather that one common approach, which I've adopted, is to simply make this clear when it occurs, with something like def my_func(somearg): """The 'somearg' argument must be Unicode.""" if not isinstance

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 5 years ago . I've recently started using Trollop, a clean and elegant command line option parser for all my small Ruby-based command line hacks. I found it was really easy to use, but getting started was difficult: despite good online documentation, there wasn't anything that showed how to

问题 What is the correct syntax for running a Node.js script with command-line arguments on Linux or Mac? To run the script with no arguments, I would simply use the command node stuff.js , but in this case, I'd like to run a script called stuff.js with the arguments "blah", "hee", "woohoo!" . 回答1: See http://nodejs.org/docs/latest/api/process.html#process_process_argv In summary you'll run it like node stuff.js blah hee "whoohoo!" Then your arguments are available in process.argv 回答2: If you want

问题 So I have been trying to get pytest to run selenium tests on different environments based on some command-line argument. But it keeps throwing this error: TypeError: setup_class() takes exactly 2 arguments (1 given) It seems that it is understanding that setup_class takes 2 arguments, but host is not being passed. Here's the code for setup_class : def setup_class(cls, host): cls.host = host And here is the conftest.py file: def pytest_addoption(parser): parser.addoption("--host", action=