C

该 Skill 汇总 malloc/free、指针、字符串、整数类型、预处理器和未定义行为等常见陷阱，给出关键规则与参考文档索引，用于辅助编写和检查更安全的 C 代码。它主要提供文字规则，不包含编译或运行工具。

热度 87.58

最近更新 2026-05-11 15:57:58

分类：开发依赖：纯提示词应用场景：代码生成 / 代码审查 / 调试排错 / 概念解释

安装技能

复制下面的话术发给你的 Agent，它会通过 secure-skills 检索并安装该技能。

执行命令安装此 skill： npx secure-skills-cli add c

Metadata

name: C
slug: c
version: 1.0.1
description: Write safe C avoiding memory corruption, buffer overflows, and undefined behavior traps.
metadata: {"clawdbot":{"emoji":"⚙️","requires":{"bins":["gcc","clang"]},"os":["linux","darwin","win32"]}}

Topic	File
malloc/free, leaks, double free	`memory.md`
Null, dangling, pointer arithmetic	`pointers.md`
Null terminator, buffer overflow	`strings.md`
Integer overflow, signed/unsigned	`types.md`
Macro traps, include guards	`preprocessor.md`
Common undefined behavior	`undefined.md`

malloc returns void* — cast required in C++, optional in C but check for NULL
free(ptr); ptr = NULL; — always null after free to prevent double-free
sizeof(array) in function gives pointer size, not array size — pass length separately
char str[5] = "hello"; — no room for null terminator, UB when used as string
strcpy doesn't check bounds — use strncpy and manually null-terminate
Signed overflow is UB — compiler can optimize assuming it never happens
i++ + i++ is UB — no sequence point between modifications
Returning pointer to local variable — dangling pointer, UB on use
#define SQUARE(x) x*x — SQUARE(1+2) = 1+2*1+2 = 5, not 9
memcpy with overlapping regions — use memmove instead
Uninitialized variables — contain garbage, UB if used
Array out of bounds — no runtime check, silent corruption or crash