UNIX
UNIX 1. What is ls –ltra ls lists the files in the current working directory - but if another directory is specified, then ls will list the files there, and in fact the user may specify any list of files and directories to be listed. Options: a) - l : long format, displaying Unix file types, permissions, number of hard links, owner, group, size, last-modified date and filename b) -t : sort the list of files by modification time.(newest first) c) -a : lists all files in the given directory, including those whose names start with "." (Which are hidden files in Unix). By default, these files are excluded from the list. d) -r : will reverse the sorting order. 2. How to rename a file abc.dat to xyz.dat $ mv abc.dat xyz.dat 3. Create a file with time stamp 2015-jan-15 $ touch -t 1501150808 xyz.dat 4. How to create empty files abc.dat and xyz.dat $ touch abc.dat $ touch xyz.dat 5. Remove a) All files in current directory $ rm * b) All files in current directory (ask confirma