How to read contents of a file from a given line number upto line number again specified by user
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:
Problem with this code is that it always returns lines from the bottom of the file. I even exchanged the commands head and tail, but of no use. While compiling the above code it shows the following:
Hello, I need help in appending the line number of each line to the file and also to get the total number of lines. Can somebody please help me.
I have a file say:
abc
def
ccc
ddd
ffff
The output should be:
Instance1=abc
Instance2=def
Instance3=ccc
Instance4=ddd
Instance5=ffff
... (2 Replies)
Hi,
I have a huge file & I want to add a specific text in column. But I want to add this text from a specific line number to a specific line number & another text in to another range of line numbers.
To be more specific: lets say my file has 1000 lines & 4 Columns. I want to add text "Hello"... (2 Replies)
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 Guys,
I am new to unix.
Actually i want help in writing an single command where
i can actually read specific line number in file where the line number will be passed to command as parameter.
ex.
1 a
2 b
3 c
4 d
And to my command i pass as 2.
so i should get output as 2 b
... (15 Replies)
I want a script that will move everything beyond a certain line number or beyond a certain content word into another file.
For example, if file A has this:
first line
second line
third line
forth line
fifth line
sixth line
I want to run a script that will move everything beyond the third... (4 Replies)
Hello Guys
Please help me with the below issue
I want to read a flat file source upto certain number of columns
Say my flat file has 30 columns but I want to read upto 25 columns only
How come the above issue can be addressed?
Thanks a lot!!!! (1 Reply)
Hi All,
I'm trying to figure out which are the trusted-ips and which are not using a script file.. I have a file named 'ip-list.txt' which contains some ip addresses and another file named 'trusted-ip-list.txt' which also contains some ip addresses. I want to read a line from... (4 Replies)
Hello everyone,
I don't really know anything about scripting, but I have to manage to make this script, out of necessity.
#!/bin/bash
while read -r line; do #I'm reading from a big wordlist
instructions using $line
done
Is there a way to automatically write the $line number the script... (4 Replies)
I am new to ksh scripts. I would like to be able to read a file line by line from a certain line number. I have a specific line number saved in a variable, say $lineNumber. How can I start reading the file from the line number saved in $lineNumber? Thanks! (4 Replies)
Hi all - I'm completely stumped by a script I'm working on...
The short version is I have a file called 'lookup' and in it are hundreds of names (first and last). I have a script that basically allows the user to enter a name, and what I need to have happen is something like this:
Record... (8 Replies)
Discussion started by: sabster
8 Replies
LEARN ABOUT MOJAVE
tail
TAIL(1) BSD General Commands Manual TAIL(1)NAME
tail -- display the last part of a file
SYNOPSIS
tail [-F | -f | -r] [-q] [-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 start-
ing 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 implies the -f option, but tail will also check to see if the file being followed has been renamed or rotated. The
file is closed and reopened when tail detects that the filename being read from has a new inode number. The -F option is ignored if
reading from standard input rather than a file.
-n number
The location is number lines.
-q Suppresses printing of headers when multiple files are being examined.
-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 unless -q flag is specified.
EXIT STATUS
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 -F, -b and -r
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 PWB UNIX.
BSD June 29, 2006 BSD