Here is an improved version of your script.
In principal a $var in a command argument sould be in quotes, like "$var", otherwise the shell tries to expand it (word splitting, globbing).
This is standard shell code. If you know awk and its hashed arrays, then a smart all-in-awk solution comes in sight...
Last edited by MadeInGermany; 05-17-2018 at 02:47 PM..
Hi,
If I use this command netstat | grep "1268" it shows me all IP addresses connected via port 1268, which is half of what I want.
I would like to be able to then map these against a PID on the system, and also thereby get the userid.
I have done a couple of days google bashing but... (3 Replies)
Hey all,
I'm looking for a command that will search a directory (and all subdirectories) and give me a file count for the number of files that contain specific characters within its filename. e.g. I want to find the number of files that contain "-a.jpg" in their name.
All the searching I've... (6 Replies)
How can I print number pyramid with for loop(not while only for) in unix like:
1
22
333
4444
55555
---------- Post updated at 09:09 AM ---------- Previous update was at 09:07 AM ----------
I forgot it is in ksh...I wrote a script in bash but it is nt wrkng in ksh...
bash script... (12 Replies)
I have a sorted file like:
Apple 3
Apple 5
Apple 8
Banana 2
Banana 3
Grape 31
Orange 7
Orange 13
I'd like to search $1 and if $1 is not the same as $1 in the previous row print that row and print the number of times $1 was found.
so the output would look like:
Apple 8 3
Banana... (2 Replies)
Ok, so I know there's a way to do this, but I've been trying to find out all afternoon with no luck. I think it should print out something like this:
1 bin
2 daemon
6 duo
Where the numbers on the left are the number of processes being run by the user whose name is listed on the right. Is... (4 Replies)
Hi,
I have a file (movies.sh), this file contains list of movies such as
I want to redirect the movies from movies.sh to file_to_process to allow me process the file with out losing anything.
I have tried
Movies.sh >> file_to_process
But I want to add the row number to the data... (2 Replies)
Hi
I have a file with number of entries
name 1 123
name 1 345
name 1 65346
name2 3243
name2 24234
name 2 234234
so on .........
how to count total number of entries for name 1 and name2...and so on Please guide. (1 Reply)
I have some files as shown below
GLL ALM 654-656 654 656
SEM LYG 655-657 655 657
SEM LYG 655-657 655 657
ALM LEG 656-658 656 658
ALM LEG 656-658 656 658
ALM LEG 656-658 656 658
LEG LEG 658-660 658 660
LEG LEG 658-660 658 660 The value of GLL is... (5 Replies)
I have a folder named test/ and under that I have multiple directories and in each of the directory I have multiple log files. I want to know how many files exists under each sub directory.
test
|--quanrantine
|--logfile1
|--logfile2
|--spooling
|--logfile1
... (4 Replies)
Discussion started by: ravikirankethe
4 Replies
LEARN ABOUT OSX
shlock
SHLOCK(1) BSD General Commands Manual SHLOCK(1)NAME
shlock -- create or verify a lock file for shell scripts
SYNOPSIS
shlock [-du] [-p PID] -f lockfile
DESCRIPTION
The shlock command can create or verify a lock file on behalf of a shell or other script program. When it attempts to create a lock file, if
one already exists, shlock verifies that it is or is not valid. If valid, shlock will exit with a non-zero exit code. If invalid, shlock
will remove the lock file, and create a new one.
shlock uses the link(2) system call to make the final target lock file, which is an atomic operation (i.e. "dot locking", so named for this
mechanism's original use for locking system mailboxes). It puts the process ID ("PID") from the command line into the requested lock file.
shlock verifies that an extant lock file is still valid by using kill(2) with a zero signal to check for the existence of the process that
holds the lock.
The -d option causes shlock to be verbose about what it is doing.
The -f argument with lockfile is always required.
The -p option with PID is given when the program is to create a lock file; when absent, shlock will simply check for the validity of the lock
file.
The -u option causes shlock to read and write the PID as a binary pid_t, instead of as ASCII, to be compatible with the locks created by
UUCP.
EXIT STATUS
A zero exit code indicates a valid lock file.
EXAMPLES
BOURNE SHELL
#!/bin/sh
lckfile=/tmp/foo.lock
if shlock -f ${lckfile} -p $$
then
# do what required the lock
rm ${lckfile}
else
echo Lock ${lckfile} already held by `cat ${lckfile}`
fi
C SHELL
#!/bin/csh -f
set lckfile=/tmp/foo.lock
shlock -f ${lckfile} -p $$
if ($status == 0) then
# do what required the lock
rm ${lckfile}
else
echo Lock ${lckfile} already held by `cat ${lckfile}`
endif
The examples assume that the file system where the lock file is to be created is writable by the user, and has space available.
HISTORY
shlock was written for the first Network News Transfer Protocol (NNTP) software distribution, released in March 1986. The algorithm was sug-
gested by Peter Honeyman, from work he did on HoneyDanBer UUCP.
AUTHORS
Erik E. Fair <fair@clock.org>
BUGS
Does not work on NFS or other network file system on different systems because the disparate systems have disjoint PID spaces.
Cannot handle the case where a lock file was not deleted, the process that created it has exited, and the system has created a new process
with the same PID as in the dead lock file. The lock file will appear to be valid even though the process is unrelated to the one that cre-
ated the lock in the first place. Always remove your lock files after you're done.
BSD June 29, 1997 BSD