Common Unix - Shell Features
Overview of common shell features. The following features are standard in every shell. List is as follows - Command Meaning > Redirect output >> Append to file < Redirect input << "Here" document (redirect input) | Pipe output & Run process in background. ; Separate commands on same line * Match any character(s) in filename ? Match single character in filename [ ] Match any characters enclosed ( ) Execute in subshell ` ` Substitute output of enclosed command " " Partial quote (allows variable and command expansion) ' ' Full quote (no expansion) \ Quote following character $var Use value for variable $$ Process id $0 Command name $n nth argument (n from 0 to 9) $* All arguments as a simple word # Begin comment bg Background execution break Break from loop statements cd Change directories continue R