c - Awkward data structure -

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i writing utility takes tab delimited text files , outputs html tables. part of functionality ability pass filter values @ command prompt. so, example, if have column "a" should able pass --filter "a" "foo" , see rows column "a" contained "foo."

this brings me question. i'm writing in c, , perhaps due inexperience language, i'm having trouble expressing "filter" data structure.

my initial stab @ problem store filters upfront:

//parse parameters , values, i.e. --start, --length (; i<argc; i++){     if (argv[i][1] == '-'){         argv[i]++; //strip long options          if (i+1 == argc || argv[i+1][0] == '-'){                 fprintf(stderr, "error: missing argument optional parameter!\n");                 exit(1);         }     }     if (strcmp(argv[i], "-start")==0)         start = strtol(argv[i+1], null, 0);     else if (strcmp(argv[i], "-length")==0)         length = strtol(argv[i+1], null, 0);     else if (strcmp(argv[i], "-filter")==0){ //store filter arguments later processing         filters = realloc(filters, sizeof(char*) * (f+2));         filters[f++] = strdup(argv[i+1]);         filters[f++] = strdup(argv[i+2]);     } }

and then, once have column names, create sparsely populated array of filter values corresponds length of file header. so, if i'm looking @ column 4, fourth value of filter array , check if populated value.

the code expands "initial" storage of filter lookup table follows:

//now know how many cols have, create sparsely populated filter array (j=0,i=0; i<ncols; i++){     filtercols = realloc(filtercols, sizeof(char*) * (ncols+1));     filtercols[i] = strdup("");     (c=0; c<f; c++){         if (strcmp(columns + j, filters[c])==0){             filtercols[i] = strdup(filters[c+1]);             break;         }     }      while (columns[j]){         j++;     }     j++; }

other being awkward, can see if specify filter has same value both column name , filter value, won't work.

in python, i'd handle dictionaries. best idiom available situation when working in c?

thank time.

you use hash:

http://uthash.sourceforge.net/


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