hi, all,
i saw a syntax like this
usr/local/mpiexec -np 8 /home/XXXX/program_exe >& ./temp/out
the output will be put into ./temp/out.
I want to know the meaning of the operation symbol '>&'.
Thanks (3 Replies)
I have a txt file with several columns and i want to peform an operation on two columns and output it to a new txt file .
file.txt
900.00000 1 1 1
500.00000
500.00000
100000.000
4
4
1.45257346E-07 899.10834 ... (4 Replies)
I use this simple command
result=$(echo "7 / 9" |bc -l)
echo $result
.77777777777777777777
.... but I like to get
0.7777777777777777777
How can I do in order to get also the 0 ?
How to use code tags when posting data and code samples. (3 Replies)
I want to perform the below division operation in shell script and round the value.
val1=6000
val2=5000
res=val1/val2 ----> 1.2---> Round to 2
Please help. (3 Replies)
I'm new to scripts, i wrote the below script to capture the percentage of FreeMemory available in Linux box. Output of UsedfreeMemory is displayed as '0'.
I'm expecting the output like 0.89 (or) .89 --- ( 0.89 perferable)
Anyone can help me on this pls.
... (3 Replies)
Hi All,
I want to display the distinct values in the file and for each distinct value how may occurance or there.
Test data:
test1.dat
20121105
20121105
20121105
20121105
20121106
20121106
20121106
20121105
I need to display the output like
Output (2 Replies)
Hi, to everybody
i have a string which Looks like this
FT47;3;1;1;;;1;09.02.2017 21:21:19;2;2
and i would like to change to value on one Position only
e.g. the values on Position 6 should change to 1 nevertheyless which values was there before
AIX 4.3.2.0 and csh
i try... (10 Replies)
Have three files. Any other approach with regards to file concatenation or splitting, etc is appreciated
If column55(billngtype) of file1 contains YMNC or YPBC then pick the value of column13(documentnumber). Now find this documentnumber in column1(Billdoc) of file2 and grep the corresponding... (4 Replies)
Discussion started by: as7951
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)