ctagget and vtagget

#include <tagUtils.h>

GAnnotations *ctagget(
        GapIO  *io,
        int     gel,
        char   *type);

GAnnotations *vtagget(
        GapIO  *io,
        int     gel,
        int     num_t,
        char  **type);

These function provides a mechanism of iterating around all the available tags of particular types on a given reading or contig number. The ctagget function searches for a single tag type, passed in type as a 4 byte string. The vtagget function searches for a set of tag types, passed as an array of num_t 4 byte strings.

To use the functions, call them with a non zero gel number and the tag type(s). The function will return a pointer to a GAnnotations structure containing the first tag on this reading or contig of this type. If none are found, NULL is returned.

To find the next tag on this reading or contig, of the same type, call the function with gel set to 0. To find all the tags of this type, keep repeating this until NULL is returned.

Returns a GAnnotations pointer for success, NULL for "not found", and (GAnnotations *)-1 for failure. The annotation pointer returned is valid until the next call of the function.

For example, the following function prints information on all vector tags for a given reading.

void print_tags(GapIO *io, int rnum) {
    char *type[] = {"SVEC", "CVEC"};
    GAnnotations *a;

    a = vtagget(io, rnum, sizeof(types)/sizeof(*types), types);

    while (a && a != (GAnnotations *)-1) {
        printf("position %d, length %d\n",
            a->position, a->length);e

        a = vtagget(io, 0, sizeof(types)/sizeof(*types), types);
    }
}