openfile
f1 = openfile(file1, &str1, &st1);
f2 = openfile(file2, &str2, &st2);
FILE * openfile(const char *, char **, struct stat *);
struct openfile *ip = input;
pad(struct openfile *ip)
gatherline(struct openfile *ip)
static char *gatherline(struct openfile *);
static char *pad(struct openfile *);
struct openfile *ip;
f_out = openfile(fn_out, "w");
f_out = openfile(fn,"w");
f = openfile(fn, "w");
ret->file = openfile(fsrc, "r");
FILE *openfile(const char *, const char *);