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Top Forums UNIX for Dummies Questions & Answers Check for Empty Command Argument Post 302136745 by Nysif Steve on Wednesday 19th of September 2007 12:10:22 PM
Old 09-19-2007
Check for Empty Command Argument

I have a script that when called can have 1 or 2 command arguments. If only 1 command argument is passed into the script how can I check that the second argument is null? I am working in Korn shell in a UNIX environment.


Example of script call with 2 arguments:
Code:
% statreport 0300 1430


Example of script call with 1 argument:
Code:
% statreport 0300

 

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service(8)						      System Manager's Manual							service(8)

NAME
service - run a System V init script SYNOPSIS
service SCRIPT COMMAND [OPTIONS] service --status-all service --help | -h | --version DESCRIPTION
service runs a System V init script in as predictable environment as possible, removing most environment variables and with current working directory set to /. The SCRIPT parameter specifies a System V init script, located in /etc/init.d/SCRIPT. The supported values of COMMAND depend on the invoked script, service passes COMMAND and OPTIONS it to the init script unmodified. All scripts should support at least the start and stop commands. As a special case, if COMMAND is --full-restart, the script is run twice, first with the stop command, then with the start command. service --status-all runs all init scripts, in alphabetical order, with the status command. If the init script file does not exist, the script tries to use legacy actions. If there is no suitable legacy action found and COMMAND is one of actions specified in LSB Core Specification, input is redirected to the systemctl. Otherwise the command fails with return code 2. FILES
/etc/init.d The directory containing System V init scripts. ENVIRONMENT
LANG, TERM The only environment variables passed to the init scripts. SEE ALSO
chkconfig(8), ntsysv(8), systemd(1), systemctl(8), systemd.service(5) Jan 2006 service(8)
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