Hello,
I am having trouble extracting a specific line from a file when the line number is known. My first attempt involved grep -n 'hi' (the word 'hi will always be there) to get the line number before the line that I actually want (line 4).
Extra Notes:
-I am working in a bash script.
-The file size is always variable, so I couldn't use head or tail.
#file that I am evaluating
I have a shell script and want to assign a value to a variable. The value is the line exctrated from a file using the line number. The line number it is not fix, and could change any time.
I have tried sed, awk, head .. See my script
# Get randome line number from the file
#selectedline = `awk... (1 Reply)
Hi Everybody,
I am trying to write a script that will get some perticuler data from a file and redirect to a file.
My Question is,
I have a Very huge file,In that file I have my required data is started from 25th line and it will ends in 100th line.
I know the line numbers, I need to get all... (9 Replies)
Hi
I want to extract certain text between two line numbers like
23234234324 and
54446655567567
How do I do this with a simple sed or awk command?
Thank you.
---------- Post updated at 06:16 PM ---------- Previous update was at 05:55 PM ----------
found it:
sed -n '#1,#2p'... (1 Reply)
Hello Everyone.
I am trying to display contains of a file from a specific line to a specific line(let say, from line number 3 to line number 5). For this I got the shell script as shown below:
if ; then
if ; then
tail +$1 $3 | head -n $2
else
... (5 Replies)
FOLKS ,
i have a text file that is generated automatically of an another korn shell script, i want to bring in the fifth line of the text file in to my korn shell script and look for a particular word in the line . Can you all share some thoughts on this one.
thanks...
Venu (3 Replies)
Dear all,
I am trying to extract a number from a line in one file (task 1), duplicate another file (task 2) and replace all instances of the strings 300, in duplicated with the extracted number (task 3). Here is what I have tried so far:
for ((k=1;k<4;k++)); do
temp=`sed -n "${k}p"... (2 Replies)
Hi,
I search all forum, but I can not find solutions of my problem :(
I have multiple files (5000 files), inside there is this data :
FILE 1:
1195.921 -898.995 0.750312E-02-0.497526E-02 0.195382E-05 0.609417E-05
-2021.287 1305.479-0.819754E-02 0.107572E-01 0.313018E-05 0.885066E-05
... (15 Replies)
I have a LOG file which looks like this
Import started at: Mon Jul 23 02:13:01 EDT 2012
Initialization completed in 2.146 seconds.
--------------------------------------------------------------------------------
--
Import summary for Import item: PolicyInformation... (8 Replies)
In the below perl code I am using tags within each line to extract certain information. The tags that are used are:
STB >0.8 is STRAND BIAS otherwise GOOD
FDP is the second number
GO towards the end of the line is read into an array and the value returned is outputed, in the first line that... (1 Reply)
Discussion started by: cmccabe
1 Replies
LEARN ABOUT NETBSD
tail
TAIL(1) BSD General Commands Manual TAIL(1)NAME
tail -- display the last part of a file
SYNOPSIS
tail [-f | -F | -r] [-b number | -c number | -n number] [file ...]
DESCRIPTION
The tail utility displays the contents of file or, by default, its standard input, to the standard output.
The display begins at a byte, line or 512-byte block location in the input. Numbers having a leading plus (``+'') sign are relative to the
beginning of the input, for example, ``-c +2'' starts the display at the second byte of the input. Numbers having a leading minus (``-'')
sign or no explicit sign are relative to the end of the input, for example, ``-n 2'' displays the last two lines of the input. The default
starting location is ``-n 10'', or the last 10 lines of the input.
The options are as follows:
-b number
The location is number 512-byte blocks.
-c number
The location is number bytes.
-f The -f option causes tail to not stop when end of file is reached, but rather to wait for additional data to be appended to the
input. The -f option is ignored if the standard input is a pipe, but not if it is a FIFO.
-F The -F option is the same as the -f option, except that every five seconds tail will check to see if the file named on the command
line has been shortened or moved (it is considered moved if the inode or device number changes) and, if so, it will close the current
file, open the filename given, print out the entire contents, and continue to wait for more data to be appended. This option is used
to follow log files though rotation by newsyslog(8) or similar programs.
-n number
The location is number lines.
-r The -r option causes the input to be displayed in reverse order, by line. Additionally, this option changes the meaning of the -b,
-c and -n options. When the -r option is specified, these options specify the number of bytes, lines or 512-byte blocks to display,
instead of the bytes, lines or blocks from the beginning or end of the input from which to begin the display. The default for the -r
option is to display all of the input.
If more than a single file is specified, each file is preceded by a header consisting of the string ``==> XXX <=='' where ``XXX'' is the name
of the file.
The tail utility exits 0 on success, and >0 if an error occurs.
SEE ALSO cat(1), head(1), sed(1)STANDARDS
The tail utility is expected to be a superset of the IEEE Std 1003.2-1992 (``POSIX.2'') specification. In particular, the -b, -r and -F
options are extensions to that standard.
The historic command line syntax of tail is supported by this implementation. The only difference between this implementation and historic
versions of tail, once the command line syntax translation has been done, is that the -b, -c and -n options modify the -r option, i.e. ``-r
-c 4'' displays the last 4 characters of the last line of the input, while the historic tail (using the historic syntax ``-4cr'') would
ignore the -c option and display the last 4 lines of the input.
HISTORY
A tail command appeared in Version 7 AT&T UNIX.
BUGS
When using the -F option, tail will not detect a file truncation if, between the truncation and the next check of the file size, data written
to the file make it larger than the last known file size.
BSD June 6, 1993 BSD