Bash script error problem Post: 302455234

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Top Forums Shell Programming and Scripting Bash script error problem Post 302455234 by methyl on Tuesday 21st of September 2010 06:30:52 AM

09-21-2010

Registered User

You may consider restructuring the script to separate the parameter validation from the processing such that the script has a beginning a middle and an end.
The actual error is caused by trying to use $num which has no value. We can prevent this by checking the value of $# first. Because there is more than one reason to reject the command line we can prepare the "usage" string in advance. In the original script the "|grep usage" has no use .
Just as an aside, your shebang line contains a lot of trailing blanks and an extra blank between the hash and /bin/bash.

Code:

#!/bin/bash
argcount=$#     # Number of arguments
num="$1"        # Value of parameter 1
usage='usage: ./area <query> ...'       # Usage string

######################
# Parameter validation
######################
if [ ${argcount} -ne 1 ]
then
        echo "${usage}"
        exit
fi
#
if [[ $num -gt 99 && $num -lt 1000 ]]
then
    :
else
    echo "${usage}"
    exit
fi

########################
# Processing starts here
########################
echo Area Codes for '"'$num'"':
grep "^$num" ~cs155/pub/area-codes | sed 's/^/   /'

########
# End
########
echo "good night"

methyl

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tcrmttest

TCRMTTEST(1)							   Tokyo Tyrant 						      TCRMTTEST(1)

NAME

       tcrmttest - test cases of the remote database API

DESCRIPTION

       The command `tcrmttest' is a utility for facility test under multi-thread situation.  This command is used in the following format.  `host'
       specifies the host name of the server.  `rnum' specifies the number of iterations.

	      tcrmttest write [-port num] [-tnum num] [-nr] [-rnd] [-ext name] host rnum
		     Store records with keys of 8 bytes.  They change as `00000001', `00000002'...
	      tcrmttest read [-port num] [-tnum num] [-mul num] host
		     Retrieve all records of the database above.
	      tcrmttest remove [-port num] [-tnum num] host
		     Remove all records of the database above.

       Options feature the following.

	      -port num : specify the port number.
	      -tnum num : specify the number of running threads.
	      -nr : use the function `tcrdbputnr' instead of `tcrdbput'.
	      -rnd : select keys at random.
	      -ext name : call a script language extension function.
	      -mul num : specify the number of records for the mget command.

       If the port number is not more than 0, UNIX domain socket is used and the path of the socket file is specified by the host parameter.  This
       command returns 0 on success, another on failure.

SEE ALSO

       ttserver(1), ttultest(1), ttulmgr(1), tcrtest(1), tcrmgr(1), ttutil(3), tcrdb(3)

Man Page							    2010-01-20							      TCRMTTEST(1)

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