i have the following process running in background:
when i give "ps -lef"
------------------------------------------------------------------------
user2
user1
user1
user3
user1
user4
user5
user4
user3
user4
user2
user1
user1
user3
user1
user4 (3 Replies)
Hi expert,
I'm using csh
Code:
#!/bin/csh
set x = 0
set number = `awk '{array=$0} END {print array;}'`
i want to use for loop to store data to $number repeatly
untill x = 23
How to use c shell for loop? (2 Replies)
I am trying to get a script working that will perform a simple database lookup using the join command.
Here are the two files that I am trying to join:
% cat lookup1.txt
Number_1 Other_data_a
Number_5 Other_data_b
Number_8 Other_data_c
Number_10 Other_data_d
% cat... (2 Replies)
I need to chmod a bunch of files with a specific extension in one directory.
If I understand correctly first I would run ls command like this
ls -R | grep .mp3 > /tmp/list
once I have the output file I should be able to run a loop to chmod all the files in the list created.
This is where... (5 Replies)
Hello!
I have somo problems with simple scripts like this:
#!/bin/bash
echo -n "Enter your name and press : "
read var_name
echo "Your name is: $var_name"
When I try to run it, this error occurs: ':not a valid identifier var_name.
Why?? (I work in cygiwin)
Is there anybody out... (10 Replies)
hello,
i'm trying to write a C-program that reads a file line by line.
(and searches each line for a given string)
This file is an special ASCII-database-file, with a lot of entries.
I checked the line with most length, and it was about 4000 characters.
With google i found several... (4 Replies)
Hi,
I'm pretty poor at using UNIX but I'm learning. Please help me with these simple problems! Much appreciated!
1. I've changed my shell from bash to csh but I prefer bash. How do I change back? I've tried using chsh -s but it's not working!
2. I'm trying to download TopCat. I've done... (2 Replies)
Dear All,
I have the following awk script.
#!/bin/bash
sh stdev.cmd data.file | awk '{print $2}' > out.data
read d < out.data
echo $d
awk '{print $1,$2- $f}' new > newz
The script runs "stdev.cmd" and output a file "out.data" and the value of the... (2 Replies)
Dear experts,
I am writing a bash script. At some point of the program I need to have 'for' loop. For simplicity I tried with some other simple code. The format of the loop is given below.
k=51
m=55
for j in {$k..$m};do
w=$(($j+2))
z=$(($j+9))
echo "$w, $z"
done
But my... (4 Replies)
Discussion started by: vjramana
4 Replies
LEARN ABOUT PHP
eval
EVAL(3) 1 EVAL(3)eval - Evaluate a string as PHP codeSYNOPSIS
mixed eval (string $code)
DESCRIPTION
Evaluates the given $code as PHP.
Caution
The eval(3) language construct is very dangerous because it allows execution of arbitrary PHP code. Its use thus is discouraged.
If you have carefully verified that there is no other option than to use this construct, pay special attention not to pass any user
provided data into it without properly validating it beforehand.
PARAMETERS
o $code
- Valid PHP code to be evaluated. The code mustn't be wrapped in opening and closing PHP tags, i.e. 'echo "Hi!";' must be passed
instead of '<? echo "Hi!"; >'. It is still possible to leave and reenter PHP mode though using the appropriate PHP tags, e.g.
'echo "In PHP mode!"; ?>In HTML mode!<? echo "Back in PHP mode!";'. Apart from that the passed code must be valid PHP. This
includes that all statements must be properly terminated using a semicolon. 'echo "Hi!"' for example will cause a parse error,
whereas 'echo "Hi!";' will work. A return statement will immediately terminate the evaluation of the code. The code will be exe-
cuted in the scope of the code calling eval(3). Thus any variables defined or changed in the eval(3) call will remain visible
after it terminates.
RETURN VALUES eval(3) returns NULL unless return is called in the evaluated code, in which case the value passed to return is returned. If there is a
parse error in the evaluated code, eval(3) returns FALSE and execution of the following code continues normally. It is not possible to
catch a parse error in eval(3) using set_error_handler(3).
EXAMPLES
Example #1
eval(3) example - simple text merge
<?php
$string = 'cup';
$name = 'coffee';
$str = 'This is a $string with my $name in it.';
echo $str. "
";
eval("$str = "$str";");
echo $str. "
";
?>
The above example will output:
This is a $string with my $name in it.
This is a cup with my coffee in it.
NOTES
Note
Because this is a language construct and not a function, it cannot be called using variable functions.
Tip
As with anything that outputs its result directly to the browser, the output-control functions can be used to capture the output of
this function, and save it in a string (for example).
Note
In case of a fatal error in the evaluated code, the whole script exits.
SEE ALSO call_user_func(3).
PHP Documentation Group EVAL(3)