Lines Matching refs:NULL
56 if (rootp == NULL)
57 return (NULL);
58 while (*rootp != NULL) { /* T1: */
67 if (q != NULL) { /* Allocate new node */
70 q->llink = q->rlink = NULL;
91 if (rootp == NULL || (p = *rootp) == NULL)
92 return (NULL);
98 if (*rootp == NULL)
99 return (NULL); /* Key not found */
102 if ((q = (*rootp)->llink) == NULL) /* Llink NULL? */
104 else if (r != NULL) { /* Rlink NULL? */
105 if (r->llink == NULL) { /* D2: Find successor */
108 } else { /* D3: Find NULL link */
109 for (q = r->llink; q->llink != NULL; q = r->llink)
134 if (root != NULL && action != NULL)
148 if (root->llink == NULL && root->rlink == NULL)
152 if (root->llink != NULL)
155 if (root->rlink != NULL)