In response to: http://meta.slashdot.org/story/12/10/11/0030249/linus-torvalds-answers-your-questions An explanation of the two different types of singly-linked list removal explained by Linus Torvalds, using the variable names introduced here: http://stackoverflow.com/questions/12914917/

linus.c

#include <stdio.h>

typedef struct ll {
  int value;
  struct ll *next;
} ll;


void print_list(ll *list_head)
{
  ll *entry = list_head;
  while (entry) {
    printf("%d\n", entry->value);
    entry = entry->next;
  }
}

#define REMOVE 1

int main()
{
  /* Create a list [1,2,3,4] */
  ll *list_head = &((ll){1, &((ll){2, &((ll){3, &((ll){4, NULL }) }) }) });
  /* Creating auto (not malloc'd) allows for auto-cleanup after removal */

  print_list(list_head);

  /* PREV VERSION *//*
  ll *prev = NULL;
  ll *entry = list_head;
  while (entry) {
    if (entry->value == REMOVE) {
      if (prev)
  prev->next = entry->next;
      else
	list_head = entry->next;
    }
    prev = entry;
    entry = entry->next;
  }*/
  
  /* LINUS VERSION */
  ll **pp = &list_head;
  while (*pp != NULL) {
    if ((*pp)->value == REMOVE) {
      (*pp) = (*pp)->next;
    } else {
      pp = &((*pp)->next);
    }
  }

  /* Print the list with the specified value removed */
  print_list(list_head);

  return 0;
}

Whoopse, forgot to log in when I posted this!