Command substitution in an echo ... - Mobile ITnT Solutions
Command substitutionCommand substitution means nothing more but to run a shell command and store its output to a variable or display back using echo command. For example, display date and time: echo "Today is $(date)"OR echo "Computer name is $(hostname)"You can use the grave accent (`) to perform a command substitution. The syntax is: `command-name`OR $(command-name)Command substitution in an echo commandecho "Text $(command-name)"OR echo -e "List of logged on users and what they are doing:\n $(w)"Command substitution and shell variablesYou can store command output to a shell variable using the following syntax: var=$(command-name)Store current date and time to a variable called NOW: NOW=$(date)echo "$NOW"Store system's host name to a variable called SERVERNAME: SERVERNAME=$(hostname)echo "Running command @ $SERVERNAME...."Store current working directory name to a variable called CWD: CWD=$(pwd)cd /path/some/where/elseecho "Current dir $(pwd) and now going back to old dir .."cd $CWDCommand substitution and shell loopsShell loop can use command substitution to get input: for f in $(ls /etc/*.conf)do echo "$f"doneHowever, a recommend syntax is as follows for file selections: for f in /etc/*.confdo echo "$f"doneResource: ................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- linux tutorial managing group access on linux and unix
- the openap project winlab
- supplemental file 1 researchgate
- introduction edu
- command substitution in an echo mobile itnt solutions
- summary and not only prof dr razvan daniel zota
- homework 3 csc 134 summer 2002 prof
- introduction to sedimentary rock texture and composition
- securitydocs comment on netcat tutorial