用C语言实现单链表的基本示例，包含了创建链表、求链表长度、输出链表、插入、删除和查找等功能，并且测试以上功能。

在C语言中，我们可以使用结构体和指针来实现单链表。以下是基本的示例代码：

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

// 定义链表节点结构
typedef struct Node {
    int data;
    struct Node* next;
} Node;

// 创建新节点并初始化
Node* createNode(int value) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    newNode->data = value;
    newNode->next = NULL;
    return newNode;
}

// 初始化空链表
Node* initList() {
    Node* head = NULL;
    return head;
}

// 插入元素到链表末尾
void insertAtEnd(Node** head, int value) {
    Node* newNode = createNode(value);
    if (*head == NULL) {
        *head = newNode;
    } else {
        Node* current = *head;
        while (current->next != NULL) {
            current = current->next;
        }
        current->next = newNode;
    }
}

// 计算链表长度
int length(Node* head) {
    int count = 0;
    Node* temp = head;
    while (temp != NULL) {
        count++;
        temp = temp->next;
    }
    return count;
}

// 输出链表
void printList(Node* head) {
    Node* temp = head;
    printf("链表内容: ");
    while (temp != NULL) {
        printf("%d ", temp->data);
        temp = temp->next;
    }
    printf("\n");
}

// 查找元素
Node* search(Node* head, int value) {
    Node* current = head;
    while (current != NULL) {
        if (current->data == value)
            return current;
        current = current->next;
    }
    return NULL;
}

// 删除节点 (仅演示了简单情况，实际删除需要考虑边界条件)
void deleteNode(Node** head, int value) {
    Node* current = *head;
    Node* previous = NULL;

    if (current != NULL && current->data == value) {
        *head = current->next;
        free(current);
        return;
    }

    while (current != NULL && current->data != value) {
        previous = current;
        current = current->next;
    }

    if (current != NULL) {
        previous->next = current->next;
        free(current);
    }
}

int main() {
    Node* list = initList();

    // 测试功能
    insertAtEnd(&list, 1);
    insertAtEnd(&list, 2);
    insertAtEnd(&list, 3);

    printList(list); // 应该输出: 链表内容: 1 2 3

    printf("链表长度: %d\n", length(list)); // 应该输出: 链表长度: 3

    Node* found = search(list, 2);
    if (found != NULL)
        printf("找到了值2的节点: %d\n", found->data);
    else
        printf("未找到值2的节点。\n");

    deleteNode(&list, 2);

    printList(list); // 删除后应输出: 链表内容: 1 3

    return 0;
}

这个程序展示了如何创建、操作和测试一个简单的单链表。请注意，在实际项目中，删除节点通常会更复杂一些，因为它涉及到处理前驱节点的情况。