UNIX UTILITY PACKAGE Shell Simulator Added Shell Commands File System Explorer ( LNC ) System Information Process Tree Viewer

What Is Shell ? Shell provides a protective covering for the kernel. A UNIX shell provides a protective outer covering. To protect the user from the complexity of the kernel, and to protect the kernel from the user, a protective shell is built around the kernel. The user makes requests to a shell, which interprets them, and passes them on to the kernel.

Shell Comparison Most contemporary versions of UNIX provide all three shells Bourne Shell C Shell Korn Shell

Functions Of Shell 1.Command line interpretation 2.Program initiation 3.Input-output redirection 4.Pipeline connection 5.Substitution of filenames 6.Maintenance of variables 7.Environment control 8.Shell programming

Our Shell Commands HelpTimeCd ShellsSysconfInode MountSysinfoWho FilesysFsblkWho –a LsLs –aLs –r Ls –ILs –lLs –ss typesLncLs –i Cd\Cd..Cpu am

help The list of implemented shell commands with a description

ls ls - Displays entries in the current working directory -l -Displays the file modes and no of links to the file,owner name, group name, size of the file (in bytes) time stamp and the file name. -a - Displays all entries including hidden files -r - Displays all entries in reverse order -i - Displays all file names with their inodes no -i - Displays the inode no of the file name specified -ss - Displays the file names in sorted order on size types - Displays all file names with their types

Shells Display existing shells in the system by reading and printing /etc/shells

Mount Display all devices and file systems mounted in the system by opening and reading /etc/mtab We use mntent structure and setmntent( ) getmntent( ) for reading the file

Mount continued FILE *fp; struct mntent *mn; fp=setmntent("/etc/mtab","r"); mn=getmntent(fp); while (mn!= NULL) { printf("%s on %s",mn->mnt_fsname,mn->mnt_dir); printf("type %s (%s)",mn->mnt_type,mn->mnt_opts); mn=getmntent(fp); } endmntent(fp);

Sysconfig Long sysconf ( int name ) Get system limits or run time options We pass macros and get integer Macros can be : _SC_ARG_MAX, _SC_CLK_TCK, _SC_OPEN_MAX, _SC_STREAM_MAX,…

Cpu We open the file /proc/cpuinfo and simply print it for geeting info about the cpu

sysinfo Using sysinfo structure and Sysinfo system call we get info about processes,memory,… int sysinfo(struct sysinfo *info);

Sysinfo continued struct sysinfo { long uptime; /* Seconds since boot */ unsigned long loads[3]; /* 1, 5, 15 min load averages */ unsigned long totalram; /* Total usable main memory size */ unsigned long freeram; /* Available memory size */ unsigned long sharedram; /* Amount of shared memory */ unsigned long bufferram; /* Memory used by buffers */ unsigned long totalswap; /* Total swap space size */ unsigned long freeswap; /* swap space still available */ unsigned short procs; /* Number of current processes */ ….. };

fsblk We want to get file system block size. The whole thing is : struct stat st; stat("/",&st); /* current fs */ printf("%d",st.st_blksize);

Am Gives info about you ; with the help of getuid(), getlogin ()

Inode Using stat structure and stat system call we get info about inode of the specified file.. struct stat { dev_t st_dev; /* device */ ino_t st_ino; /* inode */ mode_t st_mode; /* protection */ dev_t st_rdev; /* device type (if inode device) */ off_t st_size; /* total size, in bytes */ unsigned long st_blksize; /* blocksize for I/O */ unsigned long st_blocks; /* allocated blocks*/ time_t st_atime; /* time of last access */ time_t st_mtime; /* time of last modification */ time_t st_ctime; /* time of last change */ };

filesys Using struct statfs and statfs system call we get info about file system. int statfs(const char *path, struct statfs *buf); int fstatfs(int fd, struct statfs *buf);

Filesys continued struct statfs { long f_type;/* type of fs */ long f_bsize; /* opt transfer block size */ long f_blocks; /* total data blocks in fs */ long f_bfree; /* free blocks in fs */ long f_bavail; /* free blocks avail to non-superuser */ long f_files; /* total file nodes in fs */ long f_ffree; /* free file nodes in fs */ fsid_t f_fsid; /* file system id */ long f_namelen; /* maxlength of filenames */ long f_spare[6]; /* spare for later */ };

Who, Who -a Using /etc/passwd and /var/run/utmp and structures utmp and passwd we get logged in users or all users. struct utmp { short ut_type; /* type of login */ pid_t ut_pid; /* pid of login process */ char ut_line[UT_LINESIZE]; /* device name of tty - "/dev/" */ char ut_user[UT_NAMESIZE]; /* user name */ char ut_host[UT_HOSTSIZE]; /* hostname for remote login */ struct timeval ut_tv; /* time entry was made. */ int32_t ut_addr_v6[4]; /* IP address of remote host. */ …..};

Who –a continued struct passwd { char *pw_name; /* user name */ char *pw_passwd; /* user password */ uid_t pw_uid; /* user id */ gid_t pw_gid; /* group id */ char *pw_gecos; /* real name */ char *pw_dir; /* home directory */ char *pw_shell; /* shell program */ };

Time We get useful info by using tm structure and localtime(), time() system calls struct tm { int tm_sec; /* seconds */ int tm_min; /* minutes */ int tm_hour; /* hours */ int tm_mday; /* day of the month */ int tm_mon; /* month */ int tm_year; /* year */ int tm_wday; /* day of the week */ int tm_yday; /* day in the year */ int tm_isdst; /* daylight saving time */ };

Cd.. Cd\ cd OBVIOUSLY with chdir( ) !

Help,Time,Cd,Shells Help : About all shell commands that we have implemented Time : Using tm structure we get time, date, day of week and day in year Cd : File system traversal. It can handle cd \ and cd.. and cd Shells : Using /etc/shells, we list existing shells in system

Who, Who –a, mount, inode Who : Using /var/run/utmp we list logged on users Who –a : Using /etc/passwd we list all who have account Mount : Using /etc/mtab we list all mounted filesystems in mount table Inode : Inode table of file as in stat structure

Filesys, sysinfo, Sysconf, Fsblk Filesys : Using statfs structure and system call we get info about file system Sysinfo : Using sysinfo structure and system call we get info about system Sysconf : Using sysconf() system call we get information about system configuration Fsblk : File system block size

Ls, types, lnc, cpu, am Lnc : Is a file systtem explorer Ls : Has been implemented with –i, -a, - ss, -r, -l flags Types : All file with their types Cpu : CPU information Am : Current user information

Late Night Commander (LNC) GUI for file system exploration Ability to operation of files like copy, delete, remove,… Uses Curses Gives information about files and file system It can have shell capabilities

Curses The curses package is a subroutine library for terminal-independent screen- painting and input-event handling which presents a high-level screen model to the programmer, hiding differences between terminal types and doing automatic optimization of output to change one screen-full of text into another.

Curses In 10 Lines !! WINDOW *windir; initscr(); start_color(); init_pair(1,COLOR_WHITE,COLOR_BLUE); windir=newwin(26,70,3,0); box(windir,ACS_VLINE,ACS_HLINE); wattrset(windir,COLOR_PAIR(1)); mvwprintw(windir,1,1," BE BRIEF “); wrefresh(windir); endwin();

Advantages Of The Project ! 1. Portability 2. Low requirements 3. User friendly 4. All advantages of shells applies here ! 5. All advantages of a file system explorer applies to LNC ! 6. Our added shell commands

Limitataions Not a complete shell LNC and big directories LNC not complete Colors are not that properly implemented Dependence on the underlaying shell Bugs !

THANK YOU !