Hi,
Let me explain the situation.
There are many files in a directory and its sub-directories that conatin the string pattern "pa". I want to replace all such instances with the pattern "pranavagarwal"
doing a
grep "pa" `ls`
does give me all the instances of the occurence of that... (3 Replies)
Dear all,
I have the following problem (it originates in the domain of bio-inf, but it is a general problem).
I have two files of one column each and of different length: a.txt and b.txt.
a.txt contains alphanumeric strings (around 30 digit) and there are 300 rows
b.txt contains alphanumeric... (2 Replies)
I need to search and replace a particular string in a file. Only the exact match of the string should be replaced.
eg: File contents : abc abcd abcdef
--> Replace only 'abc' with 'xyz', but it should not replace abcd with xyzd.
So the o/p should be: xyz abcd abcdef.
How can this be done? I... (5 Replies)
Hi,
What should be the syntax to match and replace an exact string using sed? And not replacing any string that contain the value?
Eg.
testtest
etstetst
testetst
testtttt
etsttest
testtesttest
testtest
I only want to replace the line with exact string "testtest" with "123456"
... (2 Replies)
Hey everybody. I've got a simple problem but am unsure how to resolve it. I am using a script to edit multiple files at once. Inside the script I am using an sed command to make the changes. My problem is that I can only get it to work for stings that contain a word or words. How can I modify it to... (1 Reply)
Hi,
I need to use the regex in the replacement string in SED command.
something like
sed -e ' s/\(^\{5\}\).\{150\}\(.*\)$/\10\{30\}1\{30\}A\{60\}B\{30\}\2/' abc
which means for all the lines in file abc that starts with 5 characters, I need to replace character 6-151... (6 Replies)
Dear Unix Forum Group Members,
Please do let me know how I can replace the double pipe with single pipe recursively on single record.
Sample Input Data:
DN set|Call prefix||| Called number address nature
0||| *789|||||||ALL number types
0||| 00||||||||ALL number types
10||... (5 Replies)
I want to replace a string by contents of file.
I am trying the following sed command:
cat sample | sed "s^<enter description here>^`cat details`^"
But it is not working.
a=`cat details` and using $a will not help since it will affect the whitespaces.
What am I missing in the above sed... (5 Replies)
Hello,
Just surfed on the web for probable answers but could not get them working.
I wish to replace the string containing spaces by another phrase but below answers did not work.
My string is:
PAIN & GAIN
I wish to convert it to:
P&G
I just need it working with sed with function -i
... (6 Replies)
Discussion started by: baris35
6 Replies
LEARN ABOUT MOJAVE
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