grep command in unix/linux
Grep: grep is one of many standard UNIX utilities. It searches files for specified words or patterns. First clear the screen, then type% grep college college.txtAs you can see, grep…
who command in unix
The “who” command lets you display the users that are currently logged into your Unix computer system.whoThis is the basic who command with no command-line arguments. It shows the names…
vi editor
To Start vi: To use vi on a file, type in vi filename. If the file named filename exists, then the first page (or screen) of the file will be displayed;…
C program that takes one or more file or directory names as command line input and reports the following information on the file: i)File type ii)Number of links iii)Read, write and execute permissions iv)Time of last access
#include #include #include #include #include void main() { int fd; struct stat buf; fd=open("f5.txt",O_RDONLY|O_CREAT,600); if(fd!=-1) { if(fstat(fd,&buf)==0) { printf("mode of fileis %u",buf.st_mode); printf("n size of the file is %u",buf.st_size); printf("n…
C programs that simulate the following cp Unix commands
cp COMMAND: cp command copy files from one location to another. If the destination is an existing file, then the file is overwritten; if the destination is an existing directory, the…
C programs that simulate the following mv Unix/Linux commands
mv COMMAND:mv command which is short for move. It is used to move/rename file from one directory to another. mv command is different from cp command as it completely removes…
C program that simulates ls Command
ls COMMAND:ls command lists the files and directories under current working directory.SYNTAX:The Syntax isls [OPTIONS]… [FILE] #include #include #include #include #include void main() { DIR *dp; struct dirent *dirp; dp=opendir(".");…
Execution of various file/directory handling Unix/Linux commands
1) pwd COMMAND:pwd – Print Working Directory. pwd command prints the full filename of the current working directory.SYNTAX:The Syntax ispwd [options]2) cd COMMAND:cd command is used to change the directory.SYNTAX:The Syntax iscd…
Menu driven shell script to demonstrate the use of tail , cmp, uniq and rm commands
clear opt=y while [ $opt = y ] do clear echo "----------Menu driven program --------" echo echo echo "1. Usage of tail command " echo echo "2. Usage of cmp…
To search a pattern using grep and fgrep command
clear echo "enter the file name" read fname1 echo "enter the contents of $fname1 and press ctrl+d" cat >$fname1 echo "enter the file name 2" read fname2 echo "enter the…