nested structs

This is a discussion on nested structs within the C Programming forums, part of the General Programming Boards category; Hi, I have 3 structs that I am trying to work with. Code: typedef struct{ char time[ARRAY_SIZE]; char date[ARRAY_SIZE]; }ARRAY1, ...

  1. #1
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    nested structs

    Hi,
    I have 3 structs that I am trying to work with.
    Code:
    typedef struct{
            char time[ARRAY_SIZE];
            char date[ARRAY_SIZE];
    }ARRAY1, 2_ARRAY;
     
    typedef struct{
          char name[10];
           ARRAY1 *main;
       }first;
     
    typedef struct{
          char names[10];
           2_ARRAY *other;
        }second;
    How do I assign values to the second struct ?
    I am getting confused.

    lotta luv

  2. #2
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    2_ARRAY is not a valid name.

    Perhaps something like this?
    Code:
    first x;
    
    x.main = ... (something like malloc, perhaps)
    strcpy(x.main->time, "12:01:59");
    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  3. #3
    and the Hat of Guessing tabstop's Avatar
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    What do you mean by "assign values to the second struct"? If you had a variable of type first, then you would use .name and .main to access the char array and ARRAY1 array, respectively.

    Side question: Do you intend for ARRAY1 and 2_ARRAY to mean the same thing?

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    oh ok...whats the syntax for assigning time through the "struct second"

  5. #5
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    Quote Originally Posted by bandal27 View Post
    oh ok...whats the syntax for assigning time through the "struct second"
    Aside from the code not compiling as the name (2_ARRAY) starts with a digit, it would be similar to the first case.
    Compilers can produce warnings - make the compiler programmers happy: Use them!
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  6. #6
    Registered User slingerland3g's Avatar
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    I also would not use the variable name of "*main".

  7. #7
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    Quote Originally Posted by slingerland3g View Post
    I also would not use the variable name of "*main".
    I do agree - don't call other things than the main entry function "main".
    But that is distinct from "main" because it's inside the struct itself - it can not be used on it's own - it will always be preceded by a variable name and . or ->



    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  8. #8
    and the hat of wrongness Salem's Avatar
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    > How do I assign values to the second struct ?
    Just add more dots.

    foo.outerMember.innerMember = 1;

    foo.outerPtr->innerMember = 2;

    etc etc
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
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  9. #9
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    thank you,
    Just one last question is the malloc needed here...?

  10. #10
    and the hat of wrongness Salem's Avatar
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    If you've got pointers, then you need to make them point somewhere.

    One popular way is to use malloc.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  11. #11
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    I am trying to get this to work.
    Code:
    typedef struct{
            char time[ARRAY_SIZE];
            char date[ARRAY_SIZE];
    }ARRAY1, 2_ARRAY;
     
    typedef struct{
          char name[10];
           ARRAY1 *main;
       }first;
     
    typedef struct{
          char names[10];
           2_ARRAY *other;
        }second;
     
           struct first *ptr;
           struct second *new;
            ptr = &first_info;
            new = &second_info;
    
    strcpy(first_info.main[count].key,tokens[i]);
    I am getting this error at

    strcpy(first_info.main[count].key,tokens[i]);
    line 115: syntax error before or at: *

    Please help

  12. #12
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    CORRECTION..
    this is the code having error

    strcpy(first_info.main[count].time,tokens[i]);
    line 115: syntax error before or at: *

  13. #13
    and the hat of wrongness Salem's Avatar
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    > strcpy(first_info.main[count].key,tokens[i]);
    So is this line of code actually inside a function?

    Also, having a member called main is going to be confusing, since there's also a function with the same name.

    A complete example which we can copy/paste into a compiler is much better than simply snipping the lines which you think are relevant.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  14. #14
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    Actually the line is in the main().
    Its not in any function.

    The code is too long.

  15. #15
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    Here is the code I am trying to run
    Code:
    #include<stdio.h>
    #include<stdlib.h>
    #include<string.h>
    #include<regex.h>
     
    #define ARRAY_SIZE 340
    #define STRUCT_SIZE 340
     
    #define MAXTOKENS       256
    #define MAXLINE         1024     /* fgets buff */
    #define MINLEN          3        /* skip lines shorter as */
    #define NUL '\0'
    #define TRUE 1
    #define FALSE 0
     
    char *strtok( char *str1, const char *str2 );
    typedef struct{
            char time[ARRAY_SIZE];
            char date[ARRAY_SIZE];
    }ARRAY1,2_ARRAY;
     
    typedef struct{
          char name[10];
           ARRAY1 *main;
       }first;
     
    typedef struct{
          char db[10];
            2_ARRAY *other;
        }second;
     
    char delims[] = "=";
    char **split(char *string, char *delim);
    int trim(char *str);
     
         first first_info;
         second second_info;
     
        ARRAY1 ARRAY1_info;
          dbmARRAY1 ARRAY12_info;
    
    int main()
    {
    
     printf ("TEST \n" );
            FILE *data_txt,*dbm_txt;
            char *delim = "=";
            char **tokens = NULL;
    int i = 0, mcount = 0, lcount = 0;
            int loop;
            int sort;
            int a=0;
            int b=0;
            int j; 
    int count = 0, cnt = 0;
    char line[MAXLINE],line2[MAXLINE];
     
            struct ARRAY1 *str_ptr;   
            struct dbmARRAY1 *new_ptr;
          str_ptr = &ARRAY1_info;
          new_ptr = &ARRAY12_info;
     
           struct first *ptr;
           struct second *new;
            ptr = &first_info;
            new = &second_info;
     
            data_txt = fopen("db2cfg.txt","r");
            dbm_txt = fopen("db2cfg2.txt","r");
     int read = 0;
     while (fgets(line,100,data_txt)!=NULL)
     {
    trim(line);
     strcpy(first_info.name,"ccmlmd");
            if ((strlen(line) > 1)&&(read!=0)){
            lcount++;
            tokens = split(line, delim);
            for(i = 0; tokens[i] != NULL; i++) {
            if (i==0){
            if (tokens[i]!=NULL){
     //  printf("&#37;02d: time %s ", i, tokens[i]);
            strcpy(first_info.main[count].time,tokens[i]);
           }
          }
      if (i==1){
          if(tokens[i]!=NULL){
    //      printf("%02d: date %s", i, tokens[i]);
     strcpy(first_info.main[count].date,tokens[i]);
            }
         }
       }
      for(i = 0; tokens[i] != NULL; i++)
      free(tokens[i]);
      free(tokens);
      count++;
      lcount++;
          }
     
          for(i=0; i < count; i++) {
     printf("%d %s %s", i,first_info.main[i].time, first_info.main[i].date);
    
          }
     
      i = 0;
    fclose(data_txt);
    // start db2cfg2
     read = 0;
    while (fgets(line2,100,dbm_txt)!=NULL)
    {
    trim(line2);
    
    strcpy(second_info.db,"ccmlmd");
    //    printf("other %s",second_info.db);
            if ((strlen(line2) > 1)&&(read!=0)){
            mcount++;
            tokens = split(line2, delim);
            for(i = 0; tokens[i] != NULL; i++) {
            if (i==0){
       if (tokens[i]!=NULL){
    //   printf("%02d: time %s ", i, tokens[i]);
     strcpy(second_info.other[cnt].time,tokens[i]);
           }
          }
      if (i==1){
          if(tokens[i]!=NULL){
    //      printf("%02d: date %s", i, tokens[i]);
     strcpy(second_info.other[cnt].date,tokens[i]);
            }
         }
       }
      for(i = 0; tokens[i] != NULL; i++)
      free(tokens[i]);
      free(tokens);
      cnt++;
     } // add for(j=0 ;j<=cnt
     j = 0;
          for(j=0; j < cnt; j++) {
     printf("%d %s %s", j,second_info.other[j].time,second_info.other[j].date);
          }
     
            fclose(dbm_txt);
            return 0;
            exit(0);
     }

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