Pkzd (Implementation of a UNIX-like operating system)

PKZD: A simple implementation of a UNIX-like operating system, rewritten by UNIX V6
Note: The system's name is taken from the Game Pokemon and Zelda (note that Pkzd is not pmzd OH)
System Introduction:
Pkzd is a Unix-like operating system that is based on the simple request of a UNIX V6 rewrite, and the system is designed to be simple, so many designs are very rudimentary.
Simulation machine:
System Image pkzd.img can be run in Bochs, Qemu, and VirtualBox (the format of VirtualBox is HDD and the hard drive, just change pkzd.img to PKZD.HDD)
Hardware Support: x86 architecture
System pursuit Simple only support keyboard, display and IDE hard disk
System call: PKZD supports the following system calls:
pid_t fork (void);
int Execve (char *filename, Char **argv, char **envp);
int exit (int status);
pid_t Wait (int *status);
pid_t getpid (void);
pid_t getppid (void);
uid_t getuid (void);
uid_t geteuid (void);
gid_t getgid (void);
gid_t getegid (void);
int setpgid (void);
The function is System V, and the parent process should ensure that no child processes exist when calling this system call
int brk (UINT addr);
int creat (const char *pathname, mode_t mode);
int open (const char *pathname, int flags, mode_t mode);
int close (int fd);
int dup (int fd);
int read (int fd, char *buf, size_t CNT);
int write (int fd, const char *BUF, size_t CNT);
off_t lseek (int fd, off_t offset, int whence);
int Mknod (const char *pathname, mode_t mode, dev_t Dev);
int access (const char *pathname, mode_t mode);
int link (const char *oldpath, const char *newpath);
int unlink (const char *path);
int mkdir (const char *pathname, mode_t mode);
int rmdir (const char *pathname);
int chdir (char *pathname);
int stat (const char *pathname, struct stat *stbuf);
int Fstat (int fs, struct stat *stbuf);
Command: In order to save time, I did not write too many commands, currently only implemented the following command
Ls
The LS command only supports parameter-ACLU
Date
ChDir
Cat
File system: PKZD is using a simple inode-based file system
The FS directory has a subset of the simplest supporting files in the command
MKFS command:
MKFS Device Swapsize Inodenumber
Initializes a virtual disk, device is a virtual disk (pkzd.img), Swapsize is the number of blocks in swap space (at least 1024x768), Inodenumber is the number of inode (at least 100)
ls command:
LS Device directory
Lists all the files in the virtual disk device specified directory directories, directory must be an absolute path
RM command:
RM Device Pathname
Delete the specified file pathname of the virtual disk device, pathname must be an absolute path, pathname can be a file, special file, or empty directory
Cat command:
Cat Device Pathname
Displays the specified file pathname for the virtual disk device, pathname must be an absolute path, pathname can be a file or a special file
Link command:
./link Device Dest Source
Create a hard-link dest for source in the virtual disk, dest and source must be absolute paths
Mknod command:
./mknod Device Pathname Mode dev
Create a special file in the virtual disk pathname, pathname must be an absolute path, Dev is the device number
mode is the decimal of the value of the St_mode in the Linux struct struct STBUF
such as 16895 for the directory, 8630 for the character device, 33279 for the normal file
Add Command:
Add Device dest Source mode
Copy the normal file source in Linux (the pathname in Unix/linux) to the virtual disk's dest (absolute path in the virtual disk), the value of mode is the same as the mode in the Mknod command
Virtual disks:
The vdisk must contain kernel files/pkzd,/init, character device/dev/tty (device number must be 0), directory/bin (all commands are in this directory)
Signal:
System signals are only available in two cases, terminating or ignoring
Time:
Time is Beijing time, other time zones cannot display the time correctly. I do not know how to get the correct time zone information from the hardware, if you know please tell me.
System published in SourceForge: address as follows
https://sourceforge.net/projects/pkzd/

Pkzd (Implementation of a UNIX-like operating system)