command line arguments

[prathiksa]

how to populate a structure in command line arguments

so,

struct
{
 ---
 ---
}
int main(int argc,char**argv)
{
  

return(struct)
}

have to access the structure elements in main

[javaeyes]

I think this may be what you're trying to do. This is quick and dirty, it doesn't check for number or type of arguments. After compiling, you pass the arguments into the program like this when you execute it: ./program 21 benjamin

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc,char**argv)
{
  int age = atoi(argv[1]);
  char name[20];
  char *tempptr = argv[2];
  strcpy(name,tempptr);

  printf("age: %i \n",age);
  printf("name: %s \n",name);

  // NOW GO AHEAD AND CREATE A STRUCT AS YOU USUALLY WOULD
  return 0;
}

[Malcolm McLean]

It's rather difficult to know what you want to achieve.

Command line arguments usually need to be checked, except in a beginner environment of teaching and learning code. There might be too many or too few, they might not be valid numbers in places which demand a number, if they are valid numbers, the numbers may be out of range.
If you are doing anything at all advanced, there are usually optional arguments.

If you go onto my website, and look at the "options parser" you will see how to write something which will do all this robustly. However it's almost certainly too advanced for what you want just now.

Lets say we have

struct
{
  char name[64];
  int payrollno;
  float salary;
} EMPLOYEE;

and we want to populate that structure from a commandline argument consisting of name, number and salary. let's also say that name is a surname, and we know there will be no errors. Simply call strcpy() to duplicate the string and get the surname, atoi() to get the payroll, and atof() to get the float. The strings are in argv[1]. argv[2], and argv[3]. (argv[0] is the name of the program).