System Call provides a lightweight, cross-platform interface for performing basic system-level operations: executing shell commands, retrieving the process ID, sleeping for a specified duration, and creating files. The C++ wrapper adds convenient method overloading for std::string and ensures type-safe access to system calls.
Code reference for C and C++ APIs for the respective Fossil Logic library.
HEADER REFERENCE #
#ifndef FOSSIL_SYS_CALL_H
#define FOSSIL_SYS_CALL_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* Function to execute a system command.
* This function takes a command string as input and executes it using the
* system's command processor. The return value is the exit status of the
* command.
*/
int fossil_sys_call_execute(const char *command);
/*
* Function to get the current process ID.
* This function returns the process ID of the calling process.
* The process ID is a unique identifier for the process.
*/
int fossil_sys_call_getpid(void);
/*
* Function to sleep for a specified number of milliseconds.
* This function suspends the execution of the calling thread for the specified
* number of milliseconds.
*/
void fossil_sys_call_sleep(int milliseconds);
/*
* Function to create a new file.
* This function creates a new file with the specified filename.
* The return value is 0 on success, or a negative error code on failure.
*/
int fossil_sys_call_create_file(const char *filename);
/**
* @brief Delete a file.
*
* Removes a file from the filesystem.
*
* @param filename Path to the file to delete.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_delete_file(const char *filename);
/**
* @brief Check if a file exists.
*
* @param filename Path to the file.
* @return 1 if the file exists, 0 if not.
*/
int fossil_sys_call_file_exists(const char *filename);
/**
* @brief Create a directory.
*
* @param dirname Path of the directory to create.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_create_directory(const char *dirname);
/**
* @brief Delete a directory (optionally recursive).
*
* @param dirname Path of the directory to delete.
* @param recursive If non-zero, delete all contents recursively.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_delete_directory(const char *dirname, int recursive);
/**
* @brief Get the current working directory.
*
* @param buffer Buffer to receive the current path.
* @param size Size of the buffer.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_getcwd(char *buffer, size_t size);
/**
* @brief Change the current working directory.
*
* @param path Path to set as current working directory.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_chdir(const char *path);
/**
* @brief List files in a directory.
*
* Returns a list of filenames in a given directory.
* (Could return a dynamically allocated array of strings, or take a callback function.)
*
* @param dirname Path to the directory.
* @param out_list Pointer to array of strings (allocated by function).
* @param out_count Pointer to receive the number of entries.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_list_directory(const char *dirname, char ***out_list, size_t *out_count);
/**
* @brief Check if a path is a directory.
*
* @param path Path to check.
* @return 1 if directory, 0 if not.
*/
int fossil_sys_call_is_directory(const char *path);
/**
* @brief Check if a path is a regular file.
*
* @param path Path to check.
* @return 1 if regular file, 0 if not.
*/
int fossil_sys_call_is_file(const char *path);
/**
* @brief Terminate the current process.
*
* @param exit_code Exit code to return to the operating system.
*/
void fossil_sys_call_exit(int exit_code);
/**
* @brief Execute a command and capture output.
*
* Runs a command and stores stdout in a buffer (similar to popen).
*
* @param command Command string to execute.
* @param buffer Buffer to store output.
* @param size Size of the buffer.
* @return 0 on success, negative error code on failure.
*/
int fossil_sys_call_execute_capture(const char *command, char *buffer, size_t size);
#ifdef __cplusplus
}
#include <string>
/**
* Fossil namespace.
*/
namespace fossil {
/**
* System namespace.
*/
namespace sys {
/**
* Syscall class.
*/
class Syscall {
public:
/**
* Execute a system command.
*
* @param command The command to execute
* @return The return value of the system command.
*/
static int execute(const std::string &command) {
return fossil_sys_call_execute(command.c_str());
}
/**
* Get the current process ID.
*
* @return The current process ID.
*/
static int getpid() {
return fossil_sys_call_getpid();
}
/**
* Sleep for a specified number of milliseconds.
*
* @param milliseconds The number of milliseconds to sleep.
*/
static void sleep(int milliseconds) {
fossil_sys_call_sleep(milliseconds);
}
/**
* Create a new file.
*
* @param filename The name of the file to create.
* @return 0 on success, or a negative error code on failure.
*/
static int create_file(const std::string &filename) {
return fossil_sys_call_create_file(filename.c_str());
}
/**
* Delete a file.
*
* @param filename Path to the file to delete.
* @return 0 on success, negative error code on failure.
*/
static int delete_file(const std::string &filename) {
return fossil_sys_call_delete_file(filename.c_str());
}
/**
* Check if a file exists.
*
* @param filename Path to the file.
* @return 1 if the file exists, 0 if not.
*/
static int file_exists(const std::string &filename) {
return fossil_sys_call_file_exists(filename.c_str());
}
/**
* Create a directory.
*
* @param dirname Path of the directory to create.
* @return 0 on success, negative error code on failure.
*/
static int create_directory(const std::string &dirname) {
return fossil_sys_call_create_directory(dirname.c_str());
}
/**
* Delete a directory (optionally recursive).
*
* @param dirname Path of the directory to delete.
* @param recursive If non-zero, delete all contents recursively.
* @return 0 on success, negative error code on failure.
*/
static int delete_directory(const std::string &dirname, int recursive) {
return fossil_sys_call_delete_directory(dirname.c_str(), recursive);
}
/**
* Get the current working directory.
*
* @param buffer Buffer to receive the current path.
* @param size Size of the buffer.
* @return 0 on success, negative error code on failure.
*/
static int getcwd(std::string *buffer, size_t size) {
return fossil_sys_call_getcwd(buffer->data(), size);
}
/**
* Change the current working directory.
*
* @param path Path to set as current working directory.
* @return 0 on success, negative error code on failure.
*/
static int chdir(const std::string &path) {
return fossil_sys_call_chdir(path.c_str());
}
/**
* List files in a directory.
*
* @param dirname Path to the directory.
* @param out_list Pointer to array of strings (allocated by function).
* @param out_count Pointer to receive the number of entries.
* @return 0 on success, negative error code on failure.
*/
static int list_directory(const std::string &dirname, char ***out_list, size_t *out_count) {
return fossil_sys_call_list_directory(dirname.c_str(), out_list, out_count);
}
/**
* Check if a path is a directory.
*
* @param path Path to check.
* @return 1 if directory, 0 if not.
*/
static int is_directory(const std::string &path) {
return fossil_sys_call_is_directory(path.c_str());
}
/**
* Check if a path is a regular file.
*
* @param path Path to check.
* @return 1 if regular file, 0 if not.
*/
static int is_file(const std::string &path) {
return fossil_sys_call_is_file(path.c_str());
}
/**
* Terminate the current process.
*
* @param exit_code Exit code to return to the operating system.
*/
static void exit(int exit_code) {
fossil_sys_call_exit(exit_code);
}
/**
* Execute a command and capture output.
*
* @param command Command string to execute.
* @param buffer Buffer to store output.
* @param size Size of the buffer.
* @return 0 on success, negative error code on failure.
*/
static int execute_capture(const std::string &command, std::string *buffer) {
return fossil_sys_call_execute_capture(command.c_str(), buffer->data(), buffer->size());
}
};
}
}
#endif
#endif /* FOSSIL_SYS_FRAMEWORK_H */SAMPLE CODE C #
#include "fossil/sys/syscall.h"
#include <stdio.h>
int main() {
printf("Current PID: %d\n", fossil_sys_call_getpid());
fossil_sys_call_sleep(500); // Sleep 500ms
int status = fossil_sys_call_execute("echo Hello Fossil!");
printf("Command exit status: %d\n", status);
if (fossil_sys_call_create_file("test.txt") == 0) {
printf("File created successfully.\n");
} else {
printf("Failed to create file.\n");
}
return 0;
}
SAMPLE CODE C++ #
#include "fossil/sys/syscall.h"
#include <iostream>
#include <string>
int main() {
using namespace fossil::sys;
std::cout << "Current PID: " << Syscall::getpid() << std::endl;
Syscall::sleep(500); // Sleep 500ms
int status = Syscall::execute("echo Hello Fossil!");
std::cout << "Command exit status: " << status << std::endl;
if (Syscall::create_file("test.txt") == 0) {
std::cout << "File created successfully." << std::endl;
} else {
std::cout << "Failed to create file." << std::endl;
}
std::string cmd = "dir"; // Windows example
Syscall::execute(cmd);
return 0;
}
