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Help with reading a file in C, with fgets()/sscanf()

This is a discussion on Help with reading a file in C, with fgets()/sscanf() within the C Programming forums, part of the General Programming Boards category; I have a text file with 190 lines, that goes something like this: Code: Antigua,English,Local dialects Bahamas,English,Creole Barbados,English Belize,English,Spanish,Mayan,Carib Canada,English,French ...

  1. #1
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    Help with reading a file in C, with fgets()/sscanf()

    I have a text file with 190 lines, that goes something like this:

    Code:
    Antigua,English,Local dialects
    Bahamas,English,Creole
    Barbados,English
    Belize,English,Spanish,Mayan,Carib
    Canada,English,French
    Costa Rica,Spanish,English
    Cuba,Spanish
    First field is the country, following fields are the different languages spoken in that country.
    Since some countries have more languages than others, I am stuck trying to read the file using fgets() and sscanf().
    I'm doing this:
    Code:
    while(i < SIZE && fgets(buffer, 255, fp))
      {
        sscanf(buffer, "%[^,]%*c%[^\n]", holdName, buffer);//read the country first, and keep the rest for the languages 
        .........
        
        /* Here is where I'm lost, I want to read a language, keep the rest of the buffer to repeat until
            the buffer is empty. But obviously I'm doing it wrong */
        while(sscanf(buffer, "%[^,]%*c%[^\n]", holdLang, buffer) != '\n')
        {
          ............
        }
        i++;
      }
    Any help please?
    I have this big program to do, and can't do anything else until I am able to read the whole file.

    Thanks

  2. #2
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    Look into the strtok function. It will basically "break" the string into tokens at whatever characters you specify.
    ErickN likes this.

  3. #3
    and the hat of wrongness Salem's Avatar
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    Another way is to make use of the %n conversion in scanf
    Code:
    #include <stdio.h>
    #include <string.h>
    int main ( ) {
      char test[] = "Belize,English,Spanish,Mayan,Carib\n";
      int   pos;
      char  *p = test;
      while ( *p ) {
        char word[50];
        sscanf(p,"%[^,\n]%*c%n",word,&pos);
        printf("Found Word=%s, pos=%d\n",word,pos);
        p += pos;
      }
      return 0;
    }
    
    $ gcc -W -Wall -ansi -pedantic -O2  bar.c
    $ ./a.out 
    Found Word=Belize, pos=7
    Found Word=English, pos=8
    Found Word=Spanish, pos=8
    Found Word=Mayan, pos=6
    Found Word=Carib, pos=6
    vart and ErickN like this.
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  4. #4
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    Thank you very much to both!
    I didnt know about any of those two methods.

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