hey gents,
I'm working on something that will use snmpwalk to query the devices on my network and retreive the device name, device IP, device model and device serial. I'm using Nmap for the enumeration and sed to clean up the results for use by snmpwalk. Once i get all the data organized I'm... (8 Replies)
Hi,
I want to make sed write a part of fileA (first 7 lines) to file1 and the rest of fileA to file2 in a single call and single line in sed. If I do the following:
sed '1,7w file1; 8,$w file2' fileA
I get only one file named file1 plus all the characters following file1. If I try to use curly... (1 Reply)
Hi,
I've to do a simple job many times whenever it has been asked, just i've to log in to all of fourtien HP servers and i've to execute
ps -fu user > temp
cat temp|sendmail "xyz@z.com"
commands to send the statics of all of 14 servers over the mail to particular user id..
Though logging... (4 Replies)
Hi,
I would like to write a script with include more than 6 unix commands.
my script like below:
echo " script started"
ls -ld
bdf | grep "rama"
tail -10 log.txt
...
..
...
now, i want to run above unix commands one by one.
example:
first the ls -ld command will be... (3 Replies)
Can somebody help me in solving this..
Input data is like
0 A
1 B
2 C
3 D
0 A1
1 B1
2 C1
3 D1
0 A2
1 B2
2 C2
3 D2
Output should be like
A B C D
A1 B1 C1 D1
A2 B2 C2 D2 (7 Replies)
Hi,
I have a requirement with,
No~Dt~Notes
1~2011/08/1~"aaa
bbb
ccc
ddd
eee
fff
ggg
hhh"
Single column alone got splitted into multiple lines.
I require the output as
No~Dt~Notes
1~2011/08/1~"aaa<>bbb<>ccc<>ddd<>eee<>fff<>ggg<>hhh"
mean to say those new lines to be... (1 Reply)
Hi,
I am new to shell scripting and have a question. I would like to redirect the output of multple commands to single file, From what I read from the bash manpage and from some searching it seems it cannot be done within the shell except setting up a loop. Is it?
I am running all clearcase... (1 Reply)
Hi all,
I have a single line output like below
echo $ips
10.26.208.28 10.26.208.26 10.26.208.27
want to convert above single line output as below format. Pls advice how to do ?
10.26.208.28
10.26.208.26
10.26.208.27
Regards
Kannan (6 Replies)
here is what i want to achieve.. i have a file with below contents
cat fileName
blah blah blah
.
.DROP this
REJECT that
.
--sport 7800 -j REJECT --reject-with icmp-port-unreachable
--dport 7800 -j REJECT --reject-with icmp-port-unreachable
.
.
.
more blah blah blah
--dport 3306... (14 Replies)
I wish to generate output of two commands in the same line separated by a single white-space.
Below is my command and output in the same line.
ls -ltr fname1.out | awk '{$2=$4=$5=x; print}' | tr '\n' '\t' | tr -s ' '; cksum<fname1.out | cut -d' ' -f1
Output:
-rw-r--r--. root Aug 26 16:57... (6 Replies)
Discussion started by: mohtashims
6 Replies
LEARN ABOUT PHP
empty
EMPTY(3) 1 EMPTY(3)empty - Determine whether a variable is emptySYNOPSIS
bool empty (mixed $var)
DESCRIPTION
Determine whether a variable is considered to be empty. A variable is considered empty if it does not exist or if its value equals FALSE.
empty(3) does not generate a warning if the variable does not exist.
PARAMETERS
o $var
- Variable to be checked
Note
Prior to PHP 5.5, empty(3) only supports variables; anything else will result in a parse error. In other words, the follow-
ing will not work: empty(trim($name)). Instead, use trim($name) == false.
No warning is generated if the variable does not exist. That means empty(3) is essentially the concise equivalent to !isset($var)
|| $var == false.
RETURN VALUES
Returns FALSE if $var exists and has a non-empty, non-zero value. Otherwise returns TRUE.
The following things are considered to be empty:
o "" (an empty string)
o 0 (0 as an integer)
o 0.0 (0 as a float)
o "0" (0 as a string)
o NULL
o FALSE
o array() (an empty array)
o $var; (a variable declared, but without a value)
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 5.5.0 | |
| | |
| | empty(3) now supports expressions, rather than |
| | only variables. |
| | |
| 5.4.0 | |
| | |
| | Checking non-numeric offsets of strings returns |
| | TRUE. |
| | |
+--------+---------------------------------------------------+
EXAMPLES
Example #1
A simple empty(3) / isset(3) comparison.
<?php
$var = 0;
// Evaluates to true because $var is empty
if (empty($var)) {
echo '$var is either 0, empty, or not set at all';
}
// Evaluates as true because $var is set
if (isset($var)) {
echo '$var is set even though it is empty';
}
?>
Example #2
empty(3) on String Offsets
PHP 5.4 changes how empty(3) behaves when passed string offsets.
<?php
$expected_array_got_string = 'somestring';
var_dump(empty($expected_array_got_string['some_key']));
var_dump(empty($expected_array_got_string[0]));
var_dump(empty($expected_array_got_string['0']));
var_dump(empty($expected_array_got_string[0.5]));
var_dump(empty($expected_array_got_string['0.5']));
var_dump(empty($expected_array_got_string['0 Mostel']));
?>
Output of the above example in PHP 5.3:
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
Output of the above example in PHP 5.4:
bool(true)
bool(false)
bool(false)
bool(false)
bool(true)
bool(true)
NOTES
Note
Because this is a language construct and not a function, it cannot be called using variable functions.
Note
When using empty(3) on inaccessible object properties, the __isset() overloading method will be called, if declared.
SEE ALSO isset(3), __isset(), unset(3), array_key_exists(3), count(3), strlen(3), The type comparison tables.
PHP Documentation Group EMPTY(3)