Hi,
I am new to scripting, so any help on this would be much appreciated.
I am trying to rename a bunch of files, taking the names sequentially from a list read in another file...
# ls oldnames
file_1
file_2
file_3
# cat names
red
yellow
green
I want the files to take on the... (6 Replies)
(I think this question desearves separate thread..)
I have a problem with 'while'
I am trying to set variables by 'while' and it is fine inside, but after completting the loop all changes are lost:
> bb="kkkk - 111\nlllll - 22222\nbbbb - 4444"
> echo "$bb"
kkkk - 111
lllll - 22222
bbbb -... (3 Replies)
Hi, I have a file with the following data
-0.00000 0.00000 0.00000 F F F
0.00000 0.00000 0.80000 F F F
0.50000 0.50000 0.60000 F F F
0.50000 0.50000 0.20000 F F F
-0.00000 0.00000 0.40000 F F F
I would like to change the last 3 lines from F F F to T T T. I tried looping each line but don't... (5 Replies)
I need to do something like this:for I in var1 var2 var3 ; do
$I = "Something calculated inside the loop"
doneObviously it doesn't work...but is it possible doing that in other ways?
Thanks in advance. (6 Replies)
i am new to shell scripting. this is similar to the code which i was writing for some other work. i want the variable 'x' to have the value which it will finally have at the end of the loop ( the number of directories ). but the value of 'x' only changes inside the loop and it remains '0' out-side... (3 Replies)
Hi guys, i have an executable file that contains several records and fields. One of the records has a variable filed that must be changed each time i want to execute the file. Would it be possible that i can use a loop to change the value of that field? Suppose that the field address is:
Record... (5 Replies)
Hi, I have an N number of files in a directory. I like to write a shell script that would make identical plots for each one of these files.
The files have names such as:
t00001.dat
t00002.dat
t00003.dat
t00004.dat
t00005.dat
.
.
.
t00040.dat
i.e. the... (4 Replies)
Dear All,
I have many sub-folders but each of them have a file with same name but different data.
I want to either move or copy them into a new folder but they need to have the path of where they are coming as part of their name...
I have managed to find the files but dont know how to change... (2 Replies)
In a "for i in *FD.CPY do" loop, I need to change .CPY to .layout so the executed command would be
reclay blahFD.CPY >blahFD.layout
What do I need to do to modify a copy of i to use after the > symbol?
TIA (5 Replies)
Discussion started by: wbport
5 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)