08-06-2009
Answer 1:
A race condition is when tasks are going in parallel and sometimes the one is sooner finished than the other. Sometimes it will be ok since you expected that the 1st task will finish as 1st and the 2nd as 2nd, but sometimes it could be that the 2nd finishes earlier and so with gives you an awkward or unexpect result.
Race condition - Wikipedia, the free encyclopedia
Answer 2:
Some people use the dot "." in their $PATH. This is good for being lazy since you don't have to use dot-slash to execute a file like ./myscript. But, it can be that there might be some evil person on the box, that put's a self-made ls command in one of your directories. So when the dot in $PATH is not at the end of the list and after the dot there is for example /usr/bin, then not ls from /usr/bin will be taken but the ls from your directory, where you currently stand is. This self-made ls by the evil person can contain something funny, but it can also have very malicious code in it that you don't want to execute like deleting files, thrashing the system etc. corrupting data or exposing data outside.
I usually never have the dot in my $PATH, not even at the end. I type so much every day that I don't mind adding a ./ in front of the things I want to execute.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi,
I want to list files only from the current dir and its child dir (not from child's child dir).
i have the following files,
./ABC/1.log
./ABC/2.log
./ABC/ABC1/A.log
./ABC/ABC1/B.log
./ABC/ABC1/XYZ/A1.log
./ABC/ABC1/XYZ/A2.log
Here i want to list only the log file from current... (1 Reply)
Discussion started by: apsprabhu
1 Replies
2. Shell Programming and Scripting
Hi
I have a directory say mydir and inside it there are many files and subdirectories and also a directory called lost+found owned by root user
I want to print all files directories and subdirectorres from my directory using find command except lost+found
If i do
find . \( -name... (3 Replies)
Discussion started by: xiamin
3 Replies
3. Shell Programming and Scripting
Hi,
The proble is below:
Assume i have files starting from "process" then date/time then ".log".
ex .
process.20100504092942.log
process.20100503152213.log
process.20100430144217.log
process.20100429153644.log
process.20100428121200.log
process.20100427130746.log... (2 Replies)
Discussion started by: meetvipin
2 Replies
4. Shell Programming and Scripting
To find all the files in your home directory that have been edited in some way since the last tar file, use this command:
find . -newer backup.tar.gz
Is anyone familiar with an older solution?
looking to identify files older then 15mins across several directories.
thanks,
manny (2 Replies)
Discussion started by: mr_manny
2 Replies
5. Shell Programming and Scripting
Hi All,
Could you please help me in searching files in a better way satisfying the below conditions
I want to search files in a path whose access time is more than 5min and less than 60 min and whose Byte size is greater than zero
For this, i am using the below command, but it is... (2 Replies)
Discussion started by: sparks
2 Replies
6. Shell Programming and Scripting
Hi,
I am a little bit confusing of using find command.
Actually, I am planning to delete the files whatever the files are existing in the day before yesterday. So, I am writing the command like this.
find . -name "*.txt" -ctime -2 { here I am confusing, if I will use +2 or +1 also I am... (5 Replies)
Discussion started by: nagraju.allam
5 Replies
7. Shell Programming and Scripting
How to find all files for instance that match the permission rwxr*x--- where * is a wildcard which can be optionally asserted but all the others must match? Thanks in advance (7 Replies)
Discussion started by: stevensw
7 Replies
8. Shell Programming and Scripting
I'm trying to use regular expression arguments as variables. I have to surround the regular expression with double quotes or else it automatically expands that regular expression to whatever is in that directory.
Unfortunately when I run 'find' it further surrounds the double quotes with single... (6 Replies)
Discussion started by: stevensw
6 Replies
9. UNIX for Dummies Questions & Answers
Hello, I am using ksh93 (/usr/dt/bin/dtksh) on Solaris and am stuck when trying to use find with the -prune option.
I need to search a directory (supplied in a variable) for files matching a certain pattern, but ignore any sub-directories.
I have tried:
find ${full_path_to_dir_to_search}... (9 Replies)
Discussion started by: gary_w
9 Replies
10. UNIX for Dummies Questions & Answers
Hi,
Please give me more details on the following examples, about "mtime" option.
When I try this, I could not get the expected output, please help.
find . -mtime -1 -print
find . -mtime +1 -print
find . -mtime 1 -print
How do I get the files modified between two dates, say from... (4 Replies)
Discussion started by: Dev_Dev
4 Replies
LEARN ABOUT DEBIAN
file::find::object::rule::extending
File::Find::Object::Rule::Extending(3pm) User Contributed Perl Documentation File::Find::Object::Rule::Extending(3pm)
NAME
File::Find::Object::Rule::Extending - the mini-guide to extending File::Find::Object::Rule
SYNOPSIS
package File::Find::Object::Rule::Random;
use strict;
use warnings;
# take useful things from File::Find::Object::Rule
use base 'File::Find::Object::Rule';
# and force our crack into the main namespace
sub File::Find::Object::Rule::random () {
my $self = shift()->_force_object;
$self->exec( sub { rand > 0.5 } );
}
1;
DESCRIPTION
File::Find::Object::Rule inherits File::Find::Rule's extensibility. It is now possibile to extend it, using the following conventions.
Declare your package
package File::Find::Object::Rule::Random;
use strict;
use warnings;
Inherit methods from File::Find::Object::Rule
# take useful things from File::Find::Object::Rule
use base 'File::Find::Object::Rule';
Force your madness into the main package
# and force our crack into the main namespace
sub File::Find::Object::Rule::random () {
my $self = shift()->_force_object;
$self->exec( sub { rand > 0.5 } );
}
Yes, we're being very cavalier here and defining things into the main File::Find::Object::Rule namespace. This is due to lack of
imaginiation on my part - I simply can't find a way for the functional and oo interface to work without doing this or some kind of
inheritance, and inheritance stops you using two File::Find::Object::Rule::Foo modules together.
For this reason try and pick distinct names for your extensions. If this becomes a problem then I may institute a semi-official registry
of taken names.
Taking no arguments.
Note the null prototype on random. This is a cheat for the procedural interface to know that your sub takes no arguments, and so allows
this to happen:
find( random => in => '.' );
If you hadn't declared "random" with a null prototype it would have consumed "in" as a parameter to it, then got all confused as it doesn't
know about a '.' rule.
NOTES ABOUT THE CALLBACK
The callback can access the File::Find::Object::Result using "$self->finder->item_obj()".
AUTHOR
Richard Clamp <richardc@unixbeard.net>
COPYRIGHT
Copyright (C) 2002 Richard Clamp. All Rights Reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
File::Find::Object::Rule
File::Find::::Rule::MMagic was the first extension module for File::Find::Rule, so maybe check that out.
perl v5.14.2 2012-05-05 File::Find::Object::Rule::Extending(3pm)