That is a dangerous use of backticks and useless use of cat and discovered for yourself one of the reasons why You are correct, it splits on whitespace, not lines. (You can change this by altering the special IFS variable, but read is preferred over backticks for this anyway.)
If you want to read lines, you can do this.
This is also more efficient than cat in backticks.
It can even split tokens for you:
read also obeys IFS, so if your file was separated by commas instead of spaces, the loop would still work with a tiny change:
Hi,
I would like to output the identical line to 2 text files, ie
output='blah'
echo $output > test1.txt
echo $output > test2.txt
Is there a way I could do that output with ONE command, ie
output='blah'
echo $output > test1.txt & test2.txt (I know that doesn't work)
Thanks for any... (1 Reply)
Hi all,
Here is my requirement
I have to search 'ORA' word in out.log file,if it is present then i need to send that file (out.log) content to some mail id.If 'ORA' word is not in that file then i need to send 'load succesful' message to some mail id.
The below the shell script is not... (5 Replies)
ok..
so problem is:
I have a file that reads:
cat 123
1 and 2
3 and 4
5 and 6
I was using for loops to run through this information.
Code:
for i in `cat 123`
do
echo $i
done
shouldn't the output come as
1 and 2 (3 Replies)
Hello,
I am trying to send text to a USB to serial adaptor and then to an external speech synthesizer. I tried using the cat and echo commands with no luck. I have gotten some audio output from my synthesizer using Kermit a terminal emulator, so I am pretty sure my synthesizer and my USB to serial... (1 Reply)
echo `echo ` doesn't echoes anything. And it's logic. But
echo `echo `echo ` ` does echoes "echo". What's the logic of it? the `echo `echo ` inside of the whole (first) echo, echoes nothing, so the first echo have to echo nothing but echoes "echo"
(too much echoing :P):o (2 Replies)
Hello, I have a simple(I think) question!
Although simple, I have been unable to resolve it, so I hope someone can help! OK, here it is:
1)I have an awk script that prints something, such as:
awk '{print $2}' a > x
so x might hold the value of say '10'
2)Now, I just want to check to see if... (4 Replies)
Hey all! I'm in an intro to UNIX class at university, and we've just began writing scripts. Naturally I can't get it to do what I want.
Basic script as follows:
COMPARE1=`ls|wc -l`
tar czf archive.tgz ~/path/to/file
COMPARE2=`tar tvzf archive.tgz|wc -l`
if
then
... (7 Replies)
Hi
I want to use echo command as below
echo 'dir=' $1 ' dir|file|home'
i need output like below :
echo 'dir=' $1 ' dir|file|home' pp13dff
Output
dir=pp13dff dir|file|home (4 Replies)
Cheers!
In /etc/syslog.conf, if an error type is not specified, is it logged anywhere (most preferable is it logged to /var/log/messages) or not?
To be more precise I am interested in error and critical level messages. At default these errors are not specified in syslog.conf, and I need to... (6 Replies)
Hi,
I need to send an email in the below format:
Hi All,
body description on 12-Dec-2014
<a html table, which is there in Result.txt file>
I am using the below command
{
echo "Hi All,"
echo "body description on $var_date "
} | ( cat Result.txt ) | /usr/sbin/sendmail -oi -t
... (1 Reply)
Discussion started by: Prasannag87
1 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)