Hello ,
Common atomic operation on filesystem is mv .
Code : "while [ -f $LOCK2 ] " will fail , eventually , some day under heavy stress with concurrent access .
Correct locking should be like this :
This code will work on almost any possible combinations ( NFS , AFS , GFS , OCFS etc )
Hi,
Does anyone seen this error before..
kernel: ENOMEM in journal_alloc_journal_head, retrying.
I encounter this problem on IBM eServers where when the above error appears usually the machine is dead or hanged. Unless a hard reboot is been done. Is this something have to do with the memory... (1 Reply)
hi #!/bin/bash
SERVER=10.89.40.35
USER=xyz
PASSWD=xyz
ftp -in $SERVER<<EOF
user $USER $PASSWD
mkdir PPL
cd /path of remote dir
lcd /path of local dir
hash
bin
put <file name>
bye
<<EOF
The above ftp script i have to schedule in crontab at a particular instance of time run daily.... (2 Replies)
I am using the following code in a C Shell script to transfer files to a remote server:
ftp -n logxx.xxxx.xxx.xxx.com <<DO_FTP1
quote user $user_name
quote pass $password
ascii
put $js_file_name
bin
put $FinalZipFile
quit
DO_FTP1
This code works great except on those rare occasions... (8 Replies)
ok, so I'm trying to add a function to my local script that runs a command on a remote host. The reason why this is needed is that, there are other scripts that run different commands on the same remote host.
so the problem is that many times there are multiple scripts being run on the remote... (1 Reply)
hi, everyone.
My want to execute the shell script below per 10 seconds
PID=`pgrep java`
if
then
/home/java/java
fi
crontab wouldn't help me.
some one can give me suggestions?thanks
---------- Post updated at 07:29 AM ---------- Previous update was at 07:26 AM ----------
... (6 Replies)
Hi ,
When i hit the URL using WGET command ,it is retrying according to the number of retry we mentioned along with Wget command.
my expectation :
1) If 1st try is failed and iam retrying again before 2nd retry i have to check for "xxxxxxx" entry in the log file.
2) If "XXXXXXX" entry is... (4 Replies)
Hi,
I am new to this forum, could any one please help me to understand the LOCKFILE command with an example and what exactly it is used for and how it is used.
Thanks
Reshu289 (4 Replies)
I need to read a file line by line, then depending on the contents of each line, type in a code that will get written to an array.
The problem I have is when I ask the user to confirm the input code, if it is wrong, how do i Return to ask again?
Any thing I try increments the file to the next... (6 Replies)
Hi,
I have a process which can run one instance at a time. Currently we have multiple scripts trying to kickoff this process. I wanted to implement the semaphore mechanism to achieve this.
I was going through few examples. The below code seems to be reasonable solution.
... (5 Replies)
We encountered these error 2 times(e.g. Solaris 10 with NetWorker installed) with in the month of August, but we couldn't pin point the root cause, it might be bad sector, bad cable or software incompatibility?
Do you experience these issue or please share your understanding about this? Thanks... (0 Replies)
Discussion started by: B@S
0 Replies
LEARN ABOUT LINUX
mail-touchlock
lockfile-progs(1) Lockfile programs lockfile-progs(1)NAME
lockfile-progs - command-line programs to safely lock and unlock files and mailboxes (via liblockfile).
SYNOPSIS
mail-lock [--use-pid] [--retry retry-count]
mail-unlock
mail-touchlock [--oneshot]
lockfile-create [--use-pid] [--retry retry-count] [--lock-name] filename
lockfile-remove [--lock-name] filename
lockfile-touch [--oneshot] [--lock-name] filename
lockfile-check [--use-pid] [--lock-name] filename
DESCRIPTION
Lockfile-progs provides a set a programs that can be used to lock and unlock mailboxes and files safely (via liblockfile):
mail-lock - lock the current user's mailbox
mail-unlock - unlock the current user's mailbox
mail-touchlock - touch the lock on the current user's mailbox
lockfile-create - lock a given file
lockfile-remove - remove the lock on a given file
lockfile-touch - touch the lock on a given file
lockfile-check - check the lock on a given file
By default, the filename argument refers to the name of the file to be locked, and the name of the lockfile will be filename .lock. How-
ever, if the --lock-name argument is specified, then filename will be taken as the name of the lockfile itself.
Each of the mail locking commands attempts to lock /var/spool/mail/<user>, where <user> is the name associated with the effective user ID,
as determined by via geteuid(2).
Once a file is locked, the lock must be touched at least once every five minutes or the lock will be considered stale, and subsequent lock
attempts will succeed. Also see the --use-pid option and the lockfile_create(3) manpage.
The lockfile-check command tests whether or not a valid lock already exists.
OPTIONS -q, --quiet
Suppress any output. Success or failure will only be indicated by the exit status.
-v, --verbose
Enable diagnostic output.
-l, --lock-name
Do not append .lock to the filename. This option applies to lockfile-create, lockfile-remove, lockfile-touch, or lockfile-check.
-p, --use-pid
Write the current process id (PID) to the lockfile whenever a lockfile is created, and use that pid when checking a lock's validity.
See the lockfile_create(3) manpage for more information. This option applies to lockfile-create, lockfile-remove, lockfile-touch, and
lockfile-check.
-o, --oneshot
Touch the lock and exit immediately. This option applies to lockfile-touch and mail-touchlock. When not provided, these commands will
run forever, touching the lock once every minute until killed.
-r retry-count, --retry retry-count
Try to lock filename retry-count times before giving up. Each attempt will be delayed a bit longer than the last (in 5 second incre-
ments) until reaching a maximum delay of one minute between retries. If retry-count is unspecified, the default is 9 which will give
up after 180 seconds (3 minutes) if all 9 lock attempts fail.
EXAMPLES
Locking a file during a lengthy process:
lockfile-create /some/file
lockfile-touch /some/file &
# Save the PID of the lockfile-touch process
BADGER="$!"
do-something-important-with /some/file
kill "${BADGER}"
lockfile-remove /some/file
EXIT STATUS
0
For lockfile-check this indicates that a valid lock exists, otherwise it just indicates successful program execution.
Not 0
For lockfile-check a non-zero exit status indicates that the specified lock does not exist or is not valid. For other programs it
indicates that some problem was encountered.
SEE ALSO maillock(3)touchlock(3)mailunlock(3)lockfile_create(3)lockfile_remove(3)lockfile_touch(3)lockfile_check(3)AUTHOR
Written by Rob Browning <rlb@defaultvalue.org>
0.1.12 2008-02-10 lockfile-progs(1)