command line arguments question

This is a discussion on command line arguments question within the C Programming forums, part of the General Programming Boards category; Hey guys i need to check that exatcly 4 arguments are entered via the command line but i if i ...

  1. #1
    Musicman - Canora
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    Location
    Melbourne
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    command line arguments question

    Hey guys i need to check that exatcly 4 arguments are entered via the command line but i if i pass more or only 3 command line arguments it runs when i want it to sto executing.

    And would the if statements == NULL be a good way of checking whether the files exist and if not the case exit the program?

    Could someone double check if iv done these correctly?



    Code:
    int commandLineArguments(int argc, char **argv) 
    {   
        /* makes a local copy of argc and **argv */
    
     
       FILE *customer, *stock, *logfile; 
       
        /* declares a pointer to each file*/
    
        /* test if 4 arguments exist including the exucutable*/
    
       if(argc !=4) 
       {
         printf("please enter 3 cmd arguments!\n");
         return 1;  
         /* stop pocessing*/
       }
    
        /* attempt to open and read arg 1*/
    
       customer = fopen(argv[1], "r");
    
        /* check if custome.csv exists*/
    
       if(customer ==NULL)
       {
         printf("cannot open %s for reading\n", argv[1]);
         return 1;  
         /* can't go on*/
       }
    
         /* try to open stock.csv and read it*/
    
       stock = fopen(argv[2], "r");
      
         /* if stock.csv does not exist error*/
       
       if(stock == NULL)
       {
         printf("cannot open %s for reading\n",argv[2]);
         return 1;  
    
         /* stop processing*/
       }
    
         /* open logfile for reading */  
     
       logfile = fopen(argv[3], "r");
    
         /* check if logfile exists*/
    
       if(logfile == NULL)
       {
         printf("cannot open %s for reading\n", argv[3]);
         return 1;  
     
         /* stop processing*/
       }
       
         /* close all files */
    
         /* checking for closing file errors */
    
       if(fclose(customer)!=0 || fclose(stock) !=0 || fclose(logfile) !=0)
       {
          fprintf(stderr, "Error in closing files\n");
       }
    
       return 0;
    
        
    }

  2. #2
    ZuK
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    Code:
    if(argc !=5)  // for 4 arguments ( argv[0] is the name of the executable )
    and yes to check if the FILE * returned by fopen() is NULL is normal
    Kurt
    Last edited by ZuK; 09-29-2005 at 08:23 AM.

  3. #3
    Frequently Quite Prolix dwks's Avatar
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    Code:
    int commandLineArguments(int argc, char **argv)
    main()?
    dwk

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