10-13-2008
Some useful strings:
$$ = The PID number of the process executing the shell.
$? = Exit status variable.
$0 = The name of the command you used to call a program.
$1 = The first argument on the command line.
$2 = The second argument on the command line.
$n = The nth argument on the command line.
$* = All the arguments on the command line.
$# The number of command line arguments.
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1. Shell Programming and Scripting
How do I check if the argument passed to a script is an integer?
I am writting a script that will take to integers and want to be able to check before I go on.
I am using bourne shell.
Thanks in advance (13 Replies)
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2. Shell Programming and Scripting
Hi ,
I have file, which has the below content:
line 100
a
b
c
d
line300
a
s
d
f
s
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a
s
d
a (3 Replies)
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3. Shell Programming and Scripting
I have the below script in file read_file.ksh if ] || ]
then
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read $FILE_NAME
if ]
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echo "valid file"
else
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fi
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4. Shell Programming and Scripting
i want to write a shell script function that will ftp the files passed in the command line . i have written a shell script for ftp but how will it do for all files passed in command line argument ,
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code written by me... (5 Replies)
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5. Shell Programming and Scripting
I want to make a script which takes the number of argument, add those argument and gives output to the user, but I am not getting through...
Script that i am using is below :
#!/bin/bash
sum=0
for i in $@
do
sum=$sum+$1
echo $sum
shift
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6. Shell Programming and Scripting
I want to make a script that check for the argument passed to it and generates an error in case any character/string argument passed to it.
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7. Shell Programming and Scripting
I have a script.
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When I run like
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Hi,
Extremely new to Perl scripting, but need a quick fix without using TEXT::CSV
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9. How to Post in the The UNIX and Linux Forums
usage: myscript.sh config.json
config.json:
{
"HOST":"abc",
"DB_NM":"xyz",
"USR_NM":"asd",
"PWD":"xxx",
.........
.........
.........
........
}
myscript.sh: (2 Replies)
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10. Shell Programming and Scripting
Hi Experts,
I have been trying to work on a simple shell script that will just add the two argument passed to it. Here is what i tried :
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}
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exec(1) User Commands exec(1)
NAME
exec, eval, source - shell built-in functions to execute other commands
SYNOPSIS
sh
exec [argument...]
eval [argument...]
csh
exec command
eval argument...
source [-h] name
ksh
*exec [arg...]
*eval [arg...]
DESCRIPTION
sh
The exec command specified by the arguments is executed in place of this shell without creating a new process. Input/output arguments may
appear and, if no other arguments are given, cause the shell input/output to be modified.
The arguments to the eval built-in are read as input to the shell and the resulting command(s) executed.
csh
exec executes command in place of the current shell, which terminates.
eval reads its arguments as input to the shell and executes the resulting command(s). This is usually used to execute commands generated as
the result of command or variable substitution.
source reads commands from name. source commands may be nested, but if they are nested too deeply the shell may run out of file descrip-
tors. An error in a sourced file at any level terminates all nested source commands.
-h Place commands from the file name on the history list without executing them.
ksh
With the exec built-in, if arg is given, the command specified by the arguments is executed in place of this shell without creating a new
process. Input/output arguments may appear and affect the current process. If no arguments are given the effect of this command is to mod-
ify file descriptors as prescribed by the input/output redirection list. In this case, any file descriptor numbers greater than 2 that are
opened with this mechanism are closed when invoking another program.
The arguments to eval are read as input to the shell and the resulting command(s) executed.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
EXIT STATUS
For ksh:
If command is not found, the exit status is 127. If command is found, but is not an executable utility, the exit status is 126. If a redi-
rection error occurs, the shell exits with a value in the range 1-125. Otherwise, exec returns a zero exit status.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
csh(1), ksh(1), sh(1), attributes(5)
SunOS 5.10 17 Jul 2002 exec(1)