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POCSV file reading issue: with large amont of data
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copied!<pre><code>#include <stdio.h> #include <stdlib.h> #include <string.h> char* getfield(char* line, int num) { char* tok = line; char* result; if (line) { do { if (!--num) { tok = strchr(line, ','); if (tok == NULL) { tok = &line[strlen(line)]; } size_t fieldlen = tok - line; if (fieldlen) { result = (char*)malloc(fieldlen+1); result[fieldlen] = '\0'; strncpy(result, line, fieldlen); return result; } else { break; } } tok = strchr(line, ','); line = tok + 1; } while (tok); } result = (char*)malloc(2); strcpy(result, "0"); return result; } int main() { FILE* stream = fopen("data.csv", "r"); char line[1024]; char *pstr;int num1,num2,num3; char* value1,value2,value3; while (fgets(line, 1024, stream)) { char* tmp = strdup(line); value1=getfield(tmp, 1); value2=getfield(tmp, 2); value3=getfield(tmp, 3); num1 =strtol(value1,&pstr,10); num2 =strtol(value2,&pstr,10); num3 =strtol(value3,&pstr,10) free(value1); free(value2); free(value3); printf("Fields 1,2,3 would be 1=%d 2=%d 3=%d\n", num1,num2,num3); // NOTE strtok clobbers tmp free(tmp); } } </code></pre> <p>above is my C code to read the file....</p> <pre><code> :::: data.csv :::: 10,34,30 10,33, 23,45,23 25,,45 </code></pre> <p>above is my file..</p> <p>here my issue is I can call the function with "num" field. so that for reading of every line I suppose to call the function 3 times.. !! so the performance is too low for the large data files.. can someone help me that I can call the function at once and It will return an array.. than I can easily store and print (e.g. for the first line array[0]=10,array[1]=34,array[2]=30 )</p>

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