Singly Linked List of Integers (add, del, print)

/*
 * Linked list of integers demonstrating add node, delete node, print list, delete list
 */

#include <stdio.h>
#include <stdlib.h>

typedef struct client_t {
    int id;
    struct client_t *next;
} client_t;

/** add node to list */
client_t *addClient (client_t **p, int n)
{
    client_t *node = malloc (sizeof *node); /* allocate node */
    if (!node) {                            /* validate allocation */
        perror ("malloc-node");
        return NULL;
    }
    node->id = n;                   /* initialize members values */
    node->next = NULL;

    if (!*p)                        /* if 1st node, node is head */
        *p = node;
    else {                          /* otherwise */
        client_t *iter = *p;        /* pointer to iterate */
        while (iter->next)          /* iterate to end (or use a tail ptr) */
            iter = iter->next;
        iter->next = node;          /* add at end */
    }

    return node;    /* return new node */
}

/** delete node with value n from list (for loop) */
void deleteClient (client_t **p, int n)
{
    client_t **ppn = p;         /* pointer to pointer to node*/
    client_t *pn = *p;          /* pointer to node */

    for (; pn; ppn = &pn->next, pn = pn->next) {
        if (pn->id == n) {
            *ppn = pn->next;    /* set address to next */
            free (pn);
            break;
        }
    }
}

/** delete all nodes in list */
void deleteList (client_t *l)
{
    client_t *iter = l;
    while (iter) {
        client_t *victim = iter;
        iter = iter->next;
        free (victim);
    }
}

/** print all nodes in list */
void prn (client_t *l)
{
    if (!l) {
        puts ("list-empty");
        return;
    }
    for (client_t *n = l; n; n = n->next)
        printf (" %d", n->id);
    putchar ('\n');
}

int main (void) {

    client_t *list = NULL;              /* pointer to list initialized NULL */

    for (int i = 1; i < 11; i++)        /* add nodes clients ids 1 - 10 */
        if (!addClient (&list, i))
            return 1;

    fputs ("original ids   : ", stdout);    /* output original list */
    prn (list);

    for (int i = 1; i < 11; i+=2)       /* delete odd client ids 1,3,5,7,9 */
        deleteClient (&list, i);

    fputs ("deleted odd ids: ", stdout);    /* output modified list */
    prn (list);

    deleteList (list);                  /* free all remaining nodes */
}