I have a comma-separated record and I'd like to use sed to pull the Nth record from it.
It seems like it'd need to be something like this: sed -n 's/'"\,$1\,"'/&/p'
Am I close? (3 Replies)
does anyone have an awk one-liner to:
print the first line, the second line, then every Nth line, and the last line of a file.
Thanks,
Kenny. (5 Replies)
Hi,
I have a input file with the following entries:
1one
2two
3three
1four
2five
3six
1seven
1eight
1nine
2ten
The output should be
1one
2two
3three
1four
2five
3six (2 Replies)
Hi,
I have a input file with the following entries:
1one
2two
3three
1four
2five
3six
1seven
1eight
1nine
2ten
2eleven
2twelve
1thirteen
2fourteen
The output should be: (5 Replies)
Hi,
For my reuirement, I have to read a file from the 2nd line till the last line<EOF>.
Say,
I have a file as test.txt, which as a header record in the first line followed by records in rest of the lines.
for i in `cat test.txt`
{
echo $i
}
While doing the above loop, I have read... (5 Replies)
can you please tell me
(1) how to delete 1st and 3rd line only from a file.
(2) How to delete last 4 lines in a file that has 2 blank lines out of last 4 lines.
Thank you. (2 Replies)
Is there an awk script that can easily perform the following operation?
I have a data file that is in the format of
1944-12,5.6
1945-01,9.8
1945-02,6.7
1945-03,9.3
1945-04,5.9
1945-05,0.7
1945-06,0.0
1945-07,0.0
1945-08,0.0
1945-09,0.0
1945-10,0.2
1945-11,10.5
1945-12,22.3... (3 Replies)
Hi all,
Greetings. I am facing some troubles and hope that the professionals here could help me.
I am handling a large dataset, and part of it is like below:
1 ab139 0 752566 G A
1 ab151 0 846808 T C
1 ab142 0 854250 G A
1 ab061 0 861808 A G
1 ab043 0 873558 T G... (4 Replies)
Hi All,
I am using UNix Sun OS sun4u sparc SUNW,SPARC-Enterprise
My intention is to insert a line of text after 13th line of every file inside a particular directory.
While trying to do it for a single file , i am using sed
sed '3 i this is the 4th line' filename
sed: command garbled: 3... (5 Replies)
My file (the output of an experiment) starts off looking like this,
_____________________________________________________________
Subjects incorporated to date: 001
Data file started on machine PKSHS260-05CP
**********************************************************************
Subject 1,... (9 Replies)
Discussion started by: samonl
9 Replies
LEARN ABOUT OPENDARWIN
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 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.
-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.
DIAGNOSTICS
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 6, 1993 BSD