07-01-2013
Quote:
Originally Posted by
RudiC
What shell do you use? Read its man page!
You will find sth like [ ! -s sql_output.txt ] will do what you need.
i am using bash.
-s checks if file is emty or not?
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OPEN(1) Linux 1.x OPEN(1)
NAME
open - start a program on a new virtual terminal (VT).
SYNOPSIS
open [-c vtnumber] [-s] [-u] [-l] [-v] [--] command command_options
DESCRIPTION
open will find the first available VT, and run on it the given command with the given command options, standard input, output and error are
directed to that terminal. The current search path ($PATH) is used to find the requested command. If no command is specified then the envi-
ronment variable $SHELL is used.
OPTIONS
-c vtnumber
Use the given VT number and not the first available. Note you must have write access to the supplied VT for this to work.
-s Switch to the new VT when starting the command. The VT of the new command will be made the new current VT.
-u Figure out the owner of the current VT, and run login as that user. Suitable to be called by init. Shouldn't be used with -c or -l.
-l Make the command a login shell. A - is prepended to the name of the command to be executed.
-v Be a bit more verbose.
-w wait for command to complete. If -w and -s are used together then open will switch back to the controlling terminal when the command
completes.
-- end of options to open.
NOTE
If open is compiled with a POSIX (Gnu) getopt() and you wish to set options to the command to be run, then you must supply the end of
options -- flag before the command.
EXAMPLES
open can be used to start a shell on the next free VT, by using the command:
open bash
To start the shell as a login shell, use:
open -l bash
To get a long listing you must supply the -- separator:
open -- ls -l
SEE ALSO
login(1), doshell(8), switchto(1).
AUTHOR
Jon Tombs <jon@gtex02.us.es or jon@robots.ox.ac.uk>
-w idea from "sam".
19 Jul 1996 V1.4 OPEN(1)