comment on

LanX ++

There are many ways to ensure single instance of perl program is running. PID files are the traditional way to do it. we can also hold a lock on a file,for example the program itself. This small piece of code will do the trick:

use Fcntl ':flock';
open my $self, '<', $0 or die "Couldn't open self: $!";
flock $self, LOCK_EX | LOCK_NB or croak "This script is already runnin
+g";
[download]

One advantage over PID files is that files automatically get unlocked when the program exits. It is much easier to implement in a reliable way.

All is well

In reply to Re: Check for another running instance of the same program by vinoth.ree
in thread Check for another running instance of the same program by Narveson

Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
Want more info? How to link or How to display code and escape characters are good places to start.


good chemistry is complicated, and a little bit messy -LW
	PerlMonks