12-22-2011
[[ ]] is a Conditional Expression. Explained in the manual for your Shell in the "Conditional Expressions" section.
[ ] is a Test. Explained partially in the manual for your Shell in the "test" section then further in the manual for the "test" command.
Though there is much overlap in the syntax for basic conditions and tests, there are also major differences in the syntax for "and" and "or" etc. .
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1. Shell Programming and Scripting
Hi
Input text is
some message some message some message
Expected output is
main value1 value2 value3
Any idea how to above values in square brackets using shell scripting?
many thanks. (3 Replies)
Discussion started by: hnh
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2. Shell Programming and Scripting
So, I have no formal higher education in programming at all and am self taught. I am now wondering what would be considered best practices? Like should I hard code a variable, then compare it to what I want to know or achieve, or should I just put the commands with in the brackets?
Example, a... (5 Replies)
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Hi,
Am trying to split a string with bracket in ksh but it is not splitting it correctly.
split("Hello, Name(1), Name(2)", main,",");
How do i split correctly? (3 Replies)
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4. Shell Programming and Scripting
Related to :
thread : 34769-removing-duplicate-lines-file.html
i want to extract the words in ()
eg: string1="bla bla (aaa) aha hai (aa)"
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Discussion started by: linuxadmin
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5. Shell Programming and Scripting
here is a small script I wrote:
#! /bin/bash
if ]
then
echo "argument is null"
fi
It is giving error:
test.sh:
any idea, why is it so? (2 Replies)
Discussion started by: vina201unx2011
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6. Shell Programming and Scripting
Hi
I have to remove in a file in first column whatever is written in brackets with brackets
so one file
hgfd 123
gfhdj 483
jdgfdg 34738
the output shuld be
hgfd 123
gfhdj 483
jdgfdg 34738 (9 Replies)
Discussion started by: manigrover
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7. Shell Programming and Scripting
Is this possible? The below code not working for me.
dir=mydir
if ; then
echo "found /home/$mydir "
else
echo "Not found /home/$mydir"
fi
---------- Post updated at 05:28 AM ---------- Previous update was at 05:25 AM ----------
Its working for me now (1 Reply)
Discussion started by: anil510
1 Replies
8. Shell Programming and Scripting
Hello !
I'm using a lot the command zf% with the cursor on the first bracket of a function for example, to fold it.
Ex : I put my cursor on the first bracket
myfunction(){
# body
}
I type zf%
It become :
+-- 9 lines : myfunction()... (2 Replies)
Discussion started by: Purgator
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9. Shell Programming and Scripting
hello Friend,
In hostgroup file, i have define lots of hostgroups. I need to remove few of them without manually editing file. Need script or syntax.
I want to search particular on hostgroup_members and delete hostgoup defination of it.
for example.
define hostgroup{
hostgroup_name... (8 Replies)
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10. UNIX for Beginners Questions & Answers
I have no idea how to write ksh script, but i'm really in need of help with this. I using fedora 30 and in attempt of runnig attached script i getting those errors, i solved first error by removing excess bracket, but i do not know what should i do with other. Pls sorry for trash post. (8 Replies)
Discussion started by: NullPtr
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sh(1) General Commands Manual sh(1)
NAME
sh - overview of various system shells
SYNOPSIS
POSIX Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
Korn Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
C Shell
[command_file] [argument_list ...]
Key Shell
DESCRIPTION
Remarks
The POSIX .2 standard requires that, on a POSIX-compliant system, executing the command activates the POSIX shell (located in file on HP-UX
systems), and executing the command produces an on-line manual entry that displays the syntax of the POSIX shell command-line.
However, the command has historically been associated with the conventional Bourne shell, which could confuse some users. To meet stan-
dards requirements and also clarify the relationships of the various shells and where they reside on the system, this entry provides com-
mand-line syntax and a brief description of each shell, and lists the names of the manual entries where each shell is described in greater
detail.
The Bourne shell is removed from the system starting with HP-UX 11i Version 1.5. Please use the POSIX shell as an alternative.
Shell Descriptions
The HP-UX operating system supports the following shells:
POSIX-conforming command programming language and command interpreter
residing in file Can execute commands read from a terminal or a file. This shell conforms to current POSIX standards in
effect at the time the HP-UX system release was introduced, and is similar to the Korn shell in many respects. Similar in
many respects to the Korn shell, the POSIX shell contains a history mechanism, supports job control, and provides various
other useful features.
Korn-shell command programming language and commands interpreter
residing in file Can execute commands read from a terminal or a file. This shell, like the POSIX shell, contains a his-
tory mechanism, supports job control, and provides various other useful features.
A command language interpreter
that incorporates a command history buffer, C-language-like syntax, and job control facilities.
Restricted version of the POSIX shell command interpreter.
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
restricted version of the Korn-shell command interpreter
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
An extension of the standard Korn Shell
that uses hierarchical softkey menus and context-sensitive help.
+--------------+--------------------+
| To obtain: | Use the command: |
+--------------+--------------------+
| POSIX Shell | /usr/bin/sh ... |
| Korn Shell | /usr/bin/ksh ... |
| C Shell | /usr/bin/csh ... |
| Key Shell | /usr/bin/keysh |
+--------------+--------------------+
These shells can also be the default invocation, depending on the entry in the file. See also chsh(1).
WARNINGS
Many manual entries contain descriptions of shell behavior or describe program or application behavior similar to ``the shell'' with a ref-
erence to ``see sh(1)''.
SEE ALSO
For more information on the various individual shells, see:
keysh(1) Key Shell description.
ksh(1) Korn Shell description.
sh-posix(1) POSIX Shell description.
csh(1) C Shell description.
sh(1)