sh -x and sh -v in Linux

By: Dorris Emailed: 1610 times Printed: 2078 times    

Latest comments
By: rohit kumar - how this program is work
By: Kirti - Hi..thx for the hadoop in
By: Spijker - I have altered the code a
By: ali mohammed - why we use the java in ne
By: ali mohammed - why we use the java in ne
By: mizhelle - when I exported the data
By: raul - no output as well, i'm ge
By: Rajesh - thanx very much...
By: Suindu De - Suppose we are executing

While programming shell sometimes you need to find the errors (bugs) in shell script and correct the errors (remove errors - debug). For this purpose you can use -v and -x option with sh or bash command to debug the shell script. General syntax is as follows:
Syntax:
sh   option   { shell-script-name }
OR
bash   option   { shell-script-name }
Option can be
-v Print shell input lines as they are read.
-x After expanding each simple-command, bash displays the expanded value of PS4 system variable, followed by the command and its expanded arguments. 

Example:

$ cat > dsh1.sh
#
# Script to show debug of shell
#
tot=`expr $1 + $2`
echo $tot

Press ctrl + d to save, and run it as
$ chmod 755 dsh1.sh
$ ./dsh1.sh 4 5

9
$ sh -x dsh1.sh 4 5
#
# Script to show debug of shell
#
tot=`expr $1 + $2`
expr $1 + $2
++ expr 4 + 5
+ tot=9
echo $tot
+ echo 9
9

 

See the above output, -x shows the exact values of variables (or statements are shown on screen with values).

$ sh -v dsh1.sh 4 5

Use -v option to debug complex shell script.


Linux Home | All Linux Tutorials | Latest Linux Tutorials

Sponsored Links

If this tutorial doesn't answer your question, or you have a specific question, just ask an expert here. Post your question to get a direct answer.



Bookmark and Share

Comments(0)


Be the first one to add a comment

Your name (required):


Your email(required, will not be shown to the public):


Your sites URL (optional):


Your comments:



More Tutorials by Dorris
sum of all digits in a given number using Shell Script
sh -x and sh -v in Linux
case..esac..in Linux Shell Script
while loop in Linux Shell Script
Nested for loop in Linux Shell Script
for loop in Linux Shell Script
Multilevel if-then-else in Linux Shell Script
Nested if-else-fi in Linux Shell Script
if...else...fi in Linux Shell Script
test command or [ expr ] in Linux Shell Script
if condition in Linux Shell Script
Download Linux. Which linux and where?
Formula in Hibernate
Primary keys assigned by triggers in Hibernate
Assigned identifiers in Hibernate

More Tutorials in Linux
smskannel SMS gateway run in background
Running jar files in background in ssh window
Could not open '': No such file or directory at lib/ExtUtils/MM_Unix.pm line 2697
Can't locate ExtUtils/MakeMaker.pm in @INC ...
bash: make: command not found
apxs: command not found
bash: svn: command not found
make: Nothing to be done for `all'.
How to burn your CD / DVD ISO image using Media Creator (Adaptec/Roxio) on Windows
How to burn your CD / DVD ISO image using Nero Burning ROM (Ahead Software) on Windows
How to burn your CD / DVD ISO image using Nero Express (Ahead Software) on Windows
How to burn your CD / DVD ISO image using NISO Recorder V2 Power Toy on Windows
How to burn your CD / DVD ISO image using k3b on CentOS
Compiling and Installing software from source in Linux
Installing RPM's using the Redhat Package Manager in Linux

More Latest News
Most Viewed Articles (in Linux )
Nested if-else-fi in Linux Shell Script
Finding factorial in Shell Script
sum of all digits in a given number using Shell Script
How to use Linux?
What is a Shell Script in linux?
How to print or access value of user defined variables in Linux Shell Script
Decimal to hexadecimal converter in Shell Script
Getting System Information in Shell Script
smskannel SMS gateway run in background
How to write your first Shell Script in linux?
Variables in Linux Shell Script
How to define User defined variables in Linux Shell Script
Filter in Linux
Nested for loop in Linux Shell Script
while loop in Linux Shell Script
Most Emailed Articles (in Linux)
Nested if-else-fi in Linux Shell Script
smskannel SMS gateway run in background
if condition in Linux Shell Script
Getting System Information in Shell Script
How to burn your CD / DVD ISO image using Nero Burning ROM (Ahead Software) on Windows
test command or [ expr ] in Linux Shell Script
Check if file exists in Shell Script
Could not open '': No such file or directory at lib/ExtUtils/MM_Unix.pm line 2697
How to print or access value of user defined variables in Linux Shell Script
while loop in Linux Shell Script
sh -x and sh -v in Linux
Check for leap year in Shell Script
Formating text in Shell Script
What is a Shell Script in linux?
Quotes in Linux Shell Script