argv

Save argv to vector or string

懵懂的女人 提交于 2019-11-29 19:24:45
问题 I need to save all arguments to a vector or something like this. I'm not a programmer, so I don't know how to do it, but here's what I've got so far. I just want to call a function system to pass all arguments after. #include "stdafx.h" #include "iostream" #include "vector" #include <string> using namespace std; int main ( int argc, char *argv[] ) { for (int i=1; i<argc; i++) { if(strcmp(argv[i], "/all /renew") == 0) { system("\"\"c:\\program files\\internet explorer\\iexplore.exe\" \"www

Why does MPI_Init accept pointers to argc and argv?

情到浓时终转凉″ 提交于 2019-11-29 16:19:28
问题 this is how we use MPI_Init function int main(int argc, char **argv) { MPI_Init(&argc, &argv); … } why does MPI_Init use pointers to argc and argv instead of values of argv? 回答1: According to the answer stated here: Passing arguments via command line with MPI Most MPI implementations will remove all the mpirun-related arguments in this function so that, after calling it, you can address command line arguments as though it were a normal (non-mpirun) command execution. i.e. after mpirun -np 10

Convert char to TCHAR* argv[]

生来就可爱ヽ(ⅴ<●) 提交于 2019-11-29 15:31:25
How can I input text into TCHAR* argv[] ? OR: How can I convert from char to TCHAR* argv[] ? char randcount[] = "Hello world"; TCHAR* argv[]; argv = convert(randcount); One way to do is: char a[] = "Hello world"; USES_CONVERSION; TCHAR* b = A2T(a); /*This code did TCHAR in my project without A2T or any other converters. Char text is a some kind of array. So we can take letters one by one and put them to TCHAR. */ #include <iostream> TCHAR* Converter(char* cha) { int aa = strlen(cha); TCHAR* tmp = new TCHAR[aa+1]; for(int i = 0; i< aa+1; i++) { tmp[i]=cha[i]; } return tmp; } int main() { char*

Process argc and argv outside of main()

不问归期 提交于 2019-11-29 14:43:45
问题 If I want to keep the bulk of my code for processing command line arguments out of main (for organization and more readable code), what would be the best way to do it? void main(int argc, char* argv[]){ //lots of code here I would like to move elsewhere } 回答1: Either pass them as parameters, or store them in global variables. As long as you don't return from main and try to process them in an atexit handler or the destructor of an object at global scope, they still exist and will be fine to

How to write own isnumber() function?

拈花ヽ惹草 提交于 2019-11-29 12:34:40
I'm new to C and I'm thinking how to write this function myself. I take a parameter from command line, so it is stored in argv array and I want to decide whether it is or isn't number. What is the easiest way to do this? Thank you #include <stdio.h> int isNumber(int *param) { if (*param > 0 && *param < 128) return 1; return 0; } int main(int argc, char *argv[]) { if (argc == 2) isNumber(argv[1]); else printf("Not enought parameters."); return 0; } Read about strtol(3) . You could use it as bool isnumber(const char*s) { char* e = NULL; (void) strtol(s, &e, 0); return e != NULL && *e == (char)0;

Strange behavior of argv when passing string containing “!!!!”

爷,独闯天下 提交于 2019-11-29 11:16:19
问题 I have written a small program that takes some input parameters from *argv[] and prints them. In almost all use cases my code works perfectly fine. A problem only arises when I use more than one exclamation mark at the end of the string I want to pass as an argument ... This works: ./program -m "Hello, world!" This does NOT work: ./program -m "Hello, world!!!!" ^^ If I do this, the program output is either twice that string, or the command I entered previous to ./program. However, what I

python: sys.argv[0] meaning in official documentation

…衆ロ難τιáo~ 提交于 2019-11-29 11:13:51
Quoting from docs.python.org : " sys.argv The list of command line arguments passed to a Python script. argv[0] is the script name (it is operating system dependent whether this is a full pathname or not). If the command was executed using the -c command line option to the interpreter, argv[0] is set to the string '-c' . If no script name was passed to the Python interpreter, argv[0] is the empty string." Am I missing something, or sys.argv[0] always returns the script name, and to get '-c' I'd have to use sys.argv[1] ? I'm testing with Python 3.2 on GNU/Linux. No, if you invoke Python with -c

int main(int argc, char *argv[])

牧云@^-^@ 提交于 2019-11-29 08:00:27
If I have this: int main(int argc, char *argv[]) In the body, you can sometimes find programs using argv[1] . When do we use argv[1] over argv[0] ? Is it only when we just want to read the second argument in the command line? By convention , argv[0] is the current program's name (or path), and argv[1] through argv[argc - 1] are the command-line arguments that the user provides. However, this doesn't have to be true -- programs can OS-specific functions to bypass this requirement, and this happens often enough that you should be aware of it. (I'm not sure if there's much you can do even if you

Is argv[argc] equal to NULL Pointer [duplicate]

浪子不回头ぞ 提交于 2019-11-29 06:27:01
This question already has an answer here: argv[argc] ==? 2 answers I read an article (forgot the URL), which said that argv[argc] is a NULL pointer (contains \0 ). To check whether if its true I wrote this code, yeah it exist. What I don't understand is, why does the OS include this NULL pointer at argv[argc] . Is it useful for something else also? int main (int argc, char **argv){ while (*argv) printf ("%s\n", *argv++); return 0; } The C Standard 5.1.2.2.1/2 second mark says explicitly argv[argc] shall be a null pointer. The C++ Standard 3.6.1/2 also says explicitly The value of argv[argc]

How to find the length of argv[] in C

左心房为你撑大大i 提交于 2019-11-29 03:43:46
#include <stdio.h> #include <stdlib.h> #include <string.h> int main(int argc, char *argv[]){ int fir; //badly named loop variable char *input[] = calloc( strlen(argv), sizeof(char)); //initializing an array for( fir = 1; fir< strlen(argv); fir++){ //removing the first element of argv strcat(input, argv[fir]); // appending to input } } The error I'm getting is for line 7. It says "passing argument 1 of 'strlen' from incompatible pointer type". I get the same error for the strcat function. It also says "given a char ** but expected a const char * " for both functions. I'm trying to populate a