使用std::system()函數(shù)可執(zhí)行系統(tǒng)命令,需包含
頭文件,傳入C風(fēng)格字符串命令,如std::system("ls -l"),返回值為-1表示命令處理器不可用。
To execute a system command in C , you can use the std::system() function from the
Using std::system()
The std::system() function takes a C-string (const char*) representing the command you want to execute. It passes the string to the host environment's command processor, which runs the command and returns an integer status code.
- On Windows, it uses cmd.exe
- On Unix-like systems (Linux, macOS), it typically uses /bin/sh
Example:
#include <iostream> #include <cstdlib> int main() { // List files in current directory on Linux/macOS std::system("ls -l"); // On Windows, you might use: // std::system("dir"); return 0; } </cstdlib></iostream>
Handling the Return Value
The return value of std::system() indicates whether the command processor was available and if the command executed successfully, but not necessarily that the command itself succeeded.
- Returns -1 if the command processor is not available
- Returns other values depending on the system and command outcome
Example with error check:
int result = std::system("some_command"); if (result == -1) { std::cerr
Security and Portability Considerations
While convenient, using std::system() comes with important caveats:
- Security risk: Avoid passing user input directly into system commands to prevent command injection
- Not portable: Commands like ls , dir , or rm may not exist across platforms
- Relies on external tools: Execution depends on specific programs being installed and accessible
If you need more control, consider platform-specific APIs like fork() and exec() on Unix, or CreateProcess() on Windows.
Basically, std::system() is simple for basic tasks, but be cautious with inputs and assume nothing about the environment.
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使用std::system()函數(shù)可執(zhí)行系統(tǒng)命令,需包含頭文件,傳入C風(fēng)格字符串命令,如std::system("ls-l"),返回值為-1表示命令處理器不可用。

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