10 More Discussions You Might Find Interesting
1. UNIX for Beginners Questions & Answers
Hello,
I would like to cut the first field and the 2 last fields from the string.Please help.
Here is the example of the string.DL_FUND_FULL_20190605.txt
DL_FUND_HIS_DEL_20190605.txt
DL_FUND_HIS_TMP_DEL20190605.txt
Please noted that
DL_ --> Every files have the prefix like this.... (3 Replies)
Discussion started by: palita2601
3 Replies
2. Shell Programming and Scripting
i have file as with the below content
aaa.bbb.cc.dd
aaa.fff.bb
yyyyy.rrrrr.ggggg.iii
wwww.w.r.ty
i want the o/p as below
dd
bb
iii
ty
but i dont want to use awk. is there any other way to do this ? (5 Replies)
Discussion started by: anandgodse
5 Replies
3. Shell Programming and Scripting
Hello,
I have got a log file and would need to write a script to cut the every first and second fields of every third line.
Job Name : dummytextd_v1
Status : KILLED
TIMEDOUT 2011-05-01 05:33
Job Name : dummyttx_v1
Status : KILLED
TIMEDOUT 2011-05-03 02:33
Job Name :... (4 Replies)
Discussion started by: Kochappa
4 Replies
4. Shell Programming and Scripting
hi all
i am need to cut the name of the file which i am entering in the comand line. say abc.txt is the name of the file i need to cut only the "abc" part. when i try doing this(using cut -f1) i am getting the data that s present inside the file and the file name. pls help.... (3 Replies)
Discussion started by: din_annauniv
3 Replies
5. Shell Programming and Scripting
Hi Everyone,
I have one a.txt:
a b 001 c
b b 002 c
c c, not 002 c
The output should be
001
002
002
If i use cut -f 3 -d' ', this does not work on the 3rd line, so i thought is any way to cut the field counting from the end? or any perl thing can do this?:confused:
... (3 Replies)
Discussion started by: jimmy_y
3 Replies
6. UNIX for Advanced & Expert Users
Hello,
I had posted earlier about printing fields using AWK, but now I have a slightly different problem. I have text files in the format:
1*2,3,4,5
and wish to print the first, third, and fifth fields, including the asterisk and commas. In other words, after filtering it should look... (1 Reply)
Discussion started by: Jahn
1 Replies
7. Shell Programming and Scripting
Hi,
I am a file with the following layout.
field1|field2|field3|field4|field5|field6|field7
field1|field2|field3|field4|field5|field6|field7
field1|field2|field3|field4|field5|field6|field7
I need to write a file with the below layout
field1|field2|fieldx|field6
where fieldx =... (5 Replies)
Discussion started by: shivacbz
5 Replies
8. Shell Programming and Scripting
Hello guys.
Is there any way I can cut the last field using "cut" ???
(without putting it into a while...)
Thanks.
435 Gavea. (9 Replies)
Discussion started by: 435 Gavea
9 Replies
9. Shell Programming and Scripting
Guys,
I have a line like this: 109;201;1099010
and as you see that first field 109 and the last field starts with 109. I need to cut the rest in the last field after 109 which is 9010
How to do it? (2 Replies)
Discussion started by: sfaqih
2 Replies
10. UNIX for Dummies Questions & Answers
If I am not sure of how many fields a string has, say
STR=/homt/root/dir1/dir2/../dirn
how to use "cut -d/ -f" to get dirn ? (3 Replies)
Discussion started by: meili100
3 Replies
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)