10-03-2007
shall we call this Shell trap for the unwary?
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1. Shell Programming and Scripting
I have two do loops. When I break of the inner loop it doesn't go back to the outer loop but exit the program. (5 Replies)
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2. Shell Programming and Scripting
Folks,
In shell script, can I mention a timeout for a command execution, afterwhich I want to exit from that particular line and proceed furthur.
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******************************
cd $EXPECT_HOME
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Hey, I'm writing this bash script that will test print me many copies of the same program but with different combos of 4 variables being between 1 and 100. Here's the code:
#! /bin/bash
x=0
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do
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do
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4. Shell Programming and Scripting
Hi,
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Regards.
Silas (2 Replies)
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5. Shell Programming and Scripting
Please see the following script.
basic="a b c"
advance="d e f"
A="basic advance"
for g in $A
do
echo $g
done
The result would be obviously
basic
advance
I want to ask how can i get the following result using $A in for loop
a
b
c (5 Replies)
Discussion started by: mmunir
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6. Shell Programming and Scripting
Hi,
I need an awk command that would parse the below expression
Input Format
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7. Shell Programming and Scripting
I need help getting over this bump on how nested for loops work in shell. Say i was comparing files in a directory in any other language my for loop would look like so
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8. Shell Programming and Scripting
I have a array reference which has some number of array references inside it.The nested array references also contains the array references.
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9. Shell Programming and Scripting
Hi,
i m trying to create script which logic is like below.
if ; then
x=`cat /tmp/testoutput.log | grep STOP | wc -l`
y=`cat /tmp/testoutput.log | grep RUN | wc -l`
if ; then
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if ; then
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fi
----------------... (2 Replies)
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10. Shell Programming and Scripting
Hi,
I'm developing a script which will have a lot of options to be checked for and will be setting things / doing further things accordingly.
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Discussion started by: umar.shaikh
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trap(1) User Commands trap(1)
NAME
trap, onintr - shell built-in functions to respond to (hardware) signals
SYNOPSIS
sh
trap [ argument n [n2...]]
csh
onintr [-| label]
ksh
*trap [ arg sig [ sig2...]]
DESCRIPTION
sh
The trap command argument is to be read and executed when the shell receives numeric or symbolic signal(s) (n). (Note: argument is scanned
once when the trap is set and once when the trap is taken.) Trap commands are executed in order of signal number or corresponding symbolic
names. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. An attempt to trap on signal 11
(memory fault) produces an error. If argument is absent all trap(s) n are reset to their original values. If argument is the null string
this signal is ignored by the shell and by the commands it invokes. If n is 0 the command argument is executed on exit from the shell. The
trap command with no arguments prints a list of commands associated with each signal number.
csh
onintr controls the action of the shell on interrupts. With no arguments, onintr restores the default action of the shell on interrupts.
(The shell terminates shell scripts and returns to the terminal command input level). With the - argument, the shell ignores all inter-
rupts. With a label argument, the shell executes a goto label when an interrupt is received or a child process terminates because it was
interrupted.
ksh
trap uses arg as a command to be read and executed when the shell receives signal(s) sig. (Note that arg is scanned once when the trap is
set and once when the trap is taken.) Each sig can be given as a number or as the name of the signal. trap commands are executed in order
of signal number. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. If arg is omitted
or is -, then the trap(s) for each sig are reset to their original values. If arg is the null (the empty string, e.g., "" ) string then
this signal is ignored by the shell and by the commands it invokes. If sig is ERR then arg will be executed whenever a command has a non-
zero exit status. If sig is DEBUG then arg will be executed after each command. If sig is 0 or EXIT for a trap set outside any function
then the command arg is executed on exit from the shell. The trap command with no arguments prints a list of commands associated with each
signal number.
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.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
csh(1), exit(1), ksh(1), sh(1), attributes(5)
SunOS 5.10 23 Oct 1994 trap(1)