Sam05121988 - you cannot source a file that only has execute permissions.
One can use sudo to get around this as show below:
create a group secret_params
make your param file owned by root:secret_params with 640 permissions (rw-r----)
In sudoers allow your.script to be run by any user as group secret_params without password:
At the top of your script: switch to group secret_params if not already in it and then execute script again:
As far as the format of the params file make it var="value"
it can be sourced in the script directly eg:
Hi All,
Not sure if this would be in a dummies sectiin or advanced. I'm looking for a script if someone has doen something like this.
I have list of files -
adc_earnedpoints.20070630.txt
adc_earnedpoints.20070707.txt
adc_earnedpoints.20070714.txt
adc_earnedpoints.20070721.txt... (2 Replies)
Hi All,
Not sure if this would be in a dummies sectiin or advanced. I'm looking for a script if someone has doen something like this.
I have list of files -
adc_earnedpoints.20070630.txt
adc_earnedpoints.20070707.txt
adc_earnedpoints.20070714.txt
adc_earnedpoints.20070721.txt... (1 Reply)
I am trying to print 1st, 2nd, 13th and 14th fields of a file of line numbers from 29 to 10029. I dont know how to put this in one code. Currently I am removing the selected lines by
awk 'NR==29,NR==10029' File1 > File2
and then doing
awk '{print $1, $2, $13, $14}' File2 > File3
Can... (3 Replies)
Hi Experts,
I am tryin to read a file and while doing so i need to skip the lines which start with a hash (#) char.
I thought of using a goto command but a lot of guys on this site say its not the good way to program. Moreover I am using a ksh shell which deos not support goto command.
... (4 Replies)
I need to extract selected lines from a log file, I can use grep to pull one line matching 'x' or matching 'y', how can I run through the log printing both matching lines in order top to bottom.
i.e
line 1 xyz - not needed
line 2 User01 - needed
line 3 123 - not needed
line 4 Info - needed... (2 Replies)
Hi all,
I jut use a loop to read lines from the user and redirect it to a file.
echo "Enter the line"
while read -r LINE
do
echo $LINE >> FILE
if ;then
break
fi
done
input
app... (1 Reply)
Hello,
I am using Awk in Ubuntu 12.04
First file: I have a file like this:
SNP1 1 198.2
SNP2 1 124.5
SNP3 1 124.4
.
.
.
Second file: I have another file like this:
SNP2
SNP5
SNP10
.
.
.
I want to create a third file like my first file but keeping ONLY the SNPs that... (8 Replies)
Hello everyone,
I have thought about this for quite some time and know what I want to do but am having some trouble at it. I have a text file filled with numbers like this, there are more in the file obviously. Each number is separated by a space.
1 3 2 4 5
1 -1 1 0 -1 5The idea is... (7 Replies)
Hi Guys ,
I have two files say a1 and a2 having following contents
a1
dag
wfd
a2
dag
wfd
chire
hcm
I want to delete only the lines in a2 which are in a1 and final output of a2 should be
a2
chire
hcm (6 Replies)
Dear All,
I have a data file input.res like below. (Only six column shown here for example.)
Sequence of first column starting from 1 to 148.
Input file
1 Q0 9_August_2014_Entertainment2 0 20.14967806339729 BM25b1.0
1 Q0 13_October_2012_Page323 1 20.134224346765738 BM25b1.0
1 Q0... (2 Replies)
Discussion started by: imranrasheedamu
2 Replies
LEARN ABOUT CENTOS
flock
FLOCK(1) User Commands FLOCK(1)NAME
flock - manage locks from shell scripts
SYNOPSIS
flock [options] <file|directory> <command> [command args]
flock [options] <file|directory> -c <command>
flock [options] <file descriptor number>
DESCRIPTION
This utility manages flock(2) locks from within shell scripts or the command line.
The first and second forms wrap the lock around the executing a command, in a manner similar to su(1) or newgrp(1). It locks a specified
file or directory, which is created (assuming appropriate permissions), if it does not already exist. By default, if the lock cannot be
immediately acquired, flock waits until the lock is available.
The third form uses open file by file descriptor number. See examples how that can be used.
OPTIONS -s, --shared
Obtain a shared lock, sometimes called a read lock.
-x, -e, --exclusive
Obtain an exclusive lock, sometimes called a write lock. This is the default.
-u, --unlock
Drop a lock. This is usually not required, since a lock is automatically dropped when the file is closed. However, it may be
required in special cases, for example if the enclosed command group may have forked a background process which should not be hold-
ing the lock.
-n, --nb, --nonblock
Fail rather than wait if the lock cannot be immediately acquired. See the -E option for the exit code used.
-w, --wait, --timeout seconds
Fail if the lock cannot be acquired within seconds. Decimal fractional values are allowed. See the -E option for the exit code
used.
-o, --close
Close the file descriptor on which the lock is held before executing command . This is useful if command spawns a child process
which should not be holding the lock.
-E, --conflict-exit-code number
The exit code used when the -n option is in use, and the conflicting lock exists, or the -w option is in use, and the timeout is
reached. The default value is 1.
-c, --command command
Pass a single command, without arguments, to the shell with -c.
-h, --help
Print a help message.
-V, --version
Show version number and exit.
EXAMPLES
shell1> flock /tmp -c cat
shell2> flock -w .007 /tmp -c echo; /bin/echo $?
Set exclusive lock to directory /tmp and the second command will fail.
shell1> flock -s /tmp -c cat
shell2> flock -s -w .007 /tmp -c echo; /bin/echo $?
Set shared lock to directory /tmp and the second command will not fail. Notice that attempting to get exclusive lock with second
command would fail.
shell> flock -x local-lock-file echo 'a b c'
Grab the exclusive lock "local-lock-file" before running echo with 'a b c'.
(
flock -n 9 || exit 1
# ... commands executed under lock ...
) 9>/var/lock/mylockfile
The form is convenient inside shell scripts. The mode used to open the file doesn't matter to flock; using > or >> allows the lock-
file to be created if it does not already exist, however, write permission is required. Using < requires that the file already
exists but only read permission is required.
[ "${FLOCKER}" != "$0" ] && exec env FLOCKER="$0" flock -en "$0" "$0" "$@" || :
This is useful boilerplate code for shell scripts. Put it at the top of the shell script you want to lock and it'll automatically
lock itself on the first run. If the env var $FLOCKER is not set to the shell script that is being run, then execute flock and grab
an exclusive non-blocking lock (using the script itself as the lock file) before re-execing itself with the right arguments. It
also sets the FLOCKER env var to the right value so it doesn't run again.
EXIT STATUS
The command uses sysexits.h return values for everything else but an options -n or -w failures which return either the value given by the
-E option, or 1 by default.
AUTHOR
H. Peter Anvin <hpa@zytor.com>
COPYRIGHT
Copyright (C) 2003-2006 H. Peter Anvin.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
LAR PURPOSE.
SEE ALSO flock(2)AVAILABILITY
The flock command is part of the util-linux package and is available from Linux Kernel Archive <ftp://ftp.kernel.org/pub/linux/utils/util-
linux/>.
util-linux September 2011 FLOCK(1)