C - Reading from a file and saving the info on a variable - c

Question

im having a problem reading from these 2 files bellow, file1 and file2, and then saving their information in 2 variables.
From the file1 i want to save the name of channels, and from the file2 i want to save the name of the users and the channel where they are signed.
I was thinking of creating 2 typedef struct(shown bellow) and then create 2 variables(shown bellow) and open the files and put the info on those lists.
I also know of another way to do it which is making a 2D array like this char[100][100], the only problem with both these solutions is that I have to impose an upper limit on the amount of the channels the list/array has.
Im not sure if these are the best ways to do it or if there is a better and easier way to do it, could you guys help?
If you guys need any more information just say so, Thanks!
Edit1: i've added the read from the file1 code that i have right now and i think it is working or so it seems but my problem/question was more of is it the right way to save the information to a variable or is there a better/easier way to do it? thanks.
Channel channels[MAX_CHANNELS];
Registration registrations[MAX_REGISTRATIONS];
typedef struct{
char name_channel[20];
int id;
} Channel;
typedef struct{
char username[50];
char name_channel[20];
} Registration;
File1:
General
SO
PCD
FBD
File2:
2016-09-26 14:00:01 paul General
2016-09-26 14:01:11 mary SO
2016-09-27 10:33:17 paul SO
2016-09-27 13:32:10 rachel General
2016-09-27 13:32:12 rachel FBD
code to read the file(i have only done the file1 yet).
File *file1 = fopen("channels.txt", "r");
if(file1==NULL){ perror("Reading error: "); exit(1); } ;
char line[100];
int i = 0;
int w=0;
for(w;w<MAX_CHANNELS;w++){
channels[w].id=-1;
strcpy(channels[w].name, "n");
}
while(fgets(line, 100, file1) != NULL){
printf("Line read: %s", line);
line[ strlen(line) -1 ] = 0;
Channel a;
strcpy(a.name , line);
a.id=1;
channels[i]=a;
i++;
}
fclose(canais);
int k;
for(k=0; k<MAX_CHANNELS; k++){
if(channels[k].id!=-1)
printf("testing var with channels: %s\n", channels[k].name);
}

Answer 1

Just a few tips that might help(in the code comments) :) I think its fine the way you are doing it. I think this is extensible as well since you can add a new member to a struct if you want to enrich you data further. I have seen strtok used to parse through data quite a bit. Strtok should eliminate the need for you to overwrite the newline due to the way it works.
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#define MYSTRINGLEN (50) // In general "magic numbers"
//in code makes it hard to read, though these are fairly apparent,
//but try using #define where you can
typedef struct {
char name[MYSTRINGLEN];
// int id;
}Channel;
typedef struct {
char username[MYSTRINGLEN];
char name[MYSTRINGLEN];
} Registration;
int main(int argc, char *argv[]){
int i = 0;
//int w = 0; not needed
int k = 0;
char line[100];
Channel channels[BUFSIZ] = {{{0}}}; // num of brackets depends on num of nested data structure
Registration registrations[BUFSIZ] = {{{0}}};
/* init all to zero instead w/ bracket syntax
for (w = 0; w < BUFSIZ; w++){
channels[w].id = -1;
strcpy(channels[w].name, "n");
}
*/
FILE * file1 = fopen("channels.txt", "r");
//Many people use strtok to get done what you are doing here if you are interested
while(fgets(line,100,file1)){ // do not need to explicitly state NULL
printf("Line read %s\n", line);
line[strlen(line) -1] = 0;
//Channel a; You have already initialized a whole array of struct, just use them
strcpy(channels[i].name, line);
//a.id = 1;
//channels[i]=a;
i++;
}
fclose(file1);
for(k = 0; k < BUFSIZ; k++){
if (0 != channels[k].name[0]){ //can test if string was populated, dont need id flag
printf("testing var with channels: %s\n", channels[k].name);
}
}
return 0;
}
de here