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.
In a script , i would like to check if the argument ( $1, $2 inside the script) contain wildcard (*,? etc). how do i do it?
> script_name arg1 arg*
$1 (arg1) does not contain wildcard, but $2 (arg* )contains wildcard. how can i tell in script?
i need to do this is because :
if arg1... (3 Replies)
Here is the command in question for f in $(<uploads); do .
I only want this to execute if uploads is not empty. If uploads is empty I want the script to quit, actually before the for command. If its not apparent uploads is a text file.
Chris (3 Replies)
Hello All,
I have written shell script whcih at the max 3 parameters.
When only one commandline argument and other two command line arguments are passed as empty string like
eg : archive ' ' ' '
Then i need to check whether the commandline... (12 Replies)
How do I check if a file is empty in a sh script
I want to test in my shell script if the output file is empty and if it is do one thing and if it isnt empty do another?
any ideas? (8 Replies)
I have the list of users in user.log, under each user folder there is sub1 folder is there. i want to check whether sub1 is empty or not, if it is empty i have to skip that user user folder and iterate next user folders. i have the sample code,its not giving not proper results.
while read line... (8 Replies)
I need to check if a directory is empty using an if condition
in the pseudocode below
if ; then
else
although i looked at a few forums on this topic, I left feeling a little unclear and i could not use the command successfully
what can i substitute in the if conditon above,... (2 Replies)
If ($argv == “-debug”) then
Echo “in loop”
Endif
But this is not working. If I modify this code and remove “-“, then it works.
Similarly I am getting problem using grep command also
Grep “-debug” Filename
Can someone please help me on how to resolve these... (1 Reply)
hi,
i want to check whether a a variable contains some value or is empty in a shell script. so if the variable contains some value i want to do some job and if the variable doesnt contain any value then i need to skip that job.
here is a sample script
read_filenames.sh contains
... (5 Replies)
All,
I'm writing an argument checking block and running into an error. I want to confirm that $1 is one of two values. Here is what I have:
if ]; then
echo -e "\nPlease check your first augument. You used \"$1\"
which is not recognized. Please see usage:"
usage
... (9 Replies)
Hello
So i have that script collection, in which i have a single script to create a configuration file.
In there, i have multiple occourences of something like this:
prj_title=$(tui-read "What is the TITLE? ($prj_name):")
] && prj_title="${prj_name/_/ }"
They all work as expected, if... (5 Replies)
Discussion started by: sea
5 Replies
LEARN ABOUT REDHAT
catch
catch(n) Tcl Built-In Commands catch(n)
__________________________________________________________________________________________________________________________________________________NAME
catch - Evaluate script and trap exceptional returns
SYNOPSIS
catch script ?varName?
_________________________________________________________________DESCRIPTION
The catch command may be used to prevent errors from aborting command interpretation. Catch calls the Tcl interpreter recursively to exe-
cute script, and always returns without raising an error, regardless of any errors that might occur while executing script.
If script raises an error, catch will return a non-zero integer value corresponding to one of the exceptional return codes (see tcl.h for
the definitions of code values). If the varName argument is given, then the variable it names is set to the error message from interpret-
ing script.
If script does not raise an error, catch will return 0 (TCL_OK) and set the variable to the value returned from script.
Note that catch catches all exceptions, including those generated by break and continue as well as errors. The only errors that are not
caught are syntax errors found when the script is compiled. This is because the catch command only catches errors during runtime. When
the catch statement is compiled, the script is compiled as well and any syntax errors will generate a Tcl error.
EXAMPLES
The catch command may be used in an if to branch based on the success of a script.
if { [catch {open $someFile w} fid] } {
puts stderr "Could not open $someFile for writing
$fid"
exit 1
}
The catch command will not catch compiled syntax errors. The first time proc foo is called, the body will be compiled and a Tcl error will
be generated.
proc foo {} {
catch {expr {1 +- }}
}
KEYWORDS
catch, error
Tcl 8.0 catch(n)