man delchain (3): delete an element of a chain

SYNOPSYS

#include "mut.h"
chain_list *delchain(pthead, ptdel)
chain_list *pthead;
chain_list *ptdel;

PARAMETERS

pthead: Pointer to a chain list
ptdel: Pointer to the element to be deleted.

DESCRIPTION

delchain deletes the element of the chain_list pointed to by ptdel in the list pointed to by pthead. The list consistency is maintainded, and the element put back in the list of free blocks.

RETURN VALUE

delchain returns a pointer to the new head of list if the ptdel pointer used to belong to the list. In most case, it has the value of pthead. If the pointer doesn't belong to the list, NULL is returned.

ERROR

"*** mbk error *** delchain impossible : pointer NULL"

: At least one of the arguments are pointing to NULL, and that clear that such a pointer can't be deleted, or used for freeing.

EXAMPLE

#include "mut.h"
void delete_match(c0, c1)
chain_list *c0, *c1;
{
chain_list *t0, *t1, *next;
   for (t0 = c0; t0; t0 = next)
      for (t1 = c1; t1; t1 = t1->NEXT)
         if (t1->DATA == t0->DATA)
            next = delchain(c0, t0); 
}