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PO2D array using pointers
 

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    <p>I am attempting to read a file with some random names in the format "ADAM","MARK","JESSIE" .....</p> <p>I have some constraints, the file should be read in a function but should be accessible form the main function with no global variables. The file size and the no of names in the file are not known. This is what I have done till now. I have some difficulty with dynamic 2d array as I have not used them much.</p> <pre><code>/* Function to read from the file */ int read_names(FILE *input, char ***names, int *name_count) { int f1,size,count,i,j=0; char **name_array,*text,pos=0; /* get the file size */ f1=open("names.txt",O_RDONLY); size=lseek(f1,0,SEEK_END); close(f1); /* Reading all the characters of the file into memory */ //Since file size is known we can use block transfer text=(char *) malloc(size * sizeof(char) ); fscanf(input,"%s",text); /* Finding the no of names in the file */ for(i=0;i&lt;size;i++) { if(text[i]==',') count++; } printf("No. of names determined\n"); /* Assigning the Name count to the pointer */ name_count=(int*)malloc(sizeof(int)); *name_count=count; name_array=(char **) malloc(count * sizeof(char *)); for(i=0;i&lt;count;i++) { name_array[i]=(char*) malloc(10 *sizeof(char )); } for(i=0;i&lt;size;i++) { if(text[i]!='"') if(text[i]==',') { **name_array[pos][j]='\0'; //error here pos++; j=0; } else name_array[pos][j++]=text[i]; } printf("Names Counted\n"); printf("Total no of names: %d\n",*name_count); names=(char ***) malloc(sizeof(char **); names=&amp;name_array; return 1; } /* Main Function */ int main(int argc, char *argv[]) { FILE *fp; char ***names; int *name_count; int status; // Opening the file fp = fopen("names.txt","r"); // Now read from file status = read_names(fp,names,name_count); printf("From Main\n"); fclose(fp); system("PAUSE"); return 0; } </code></pre> <p>I use WxDev and am getting an error "invalid type argument of `unary *' when I try to assign the null character. </p> <p>Any pointers on how to do this?</p>
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    1. COYou might want to try formatting your code, as it's hard for others to read in its present form.
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      1. USPaul R
    2. COThe fact that you open 'names.txt' twice should indicate to you there is some kind of problem.
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    3. COwhat is the use of char*** name in the function read_names?
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      1. USManoj R
 

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