Sponsored Content
Homework and Emergencies Emergency UNIX and Linux Support Replace nth position character of all the lines in file Post 302676029 by elixir_sinari on Tuesday 24th of July 2012 02:43:43 AM
Old 07-24-2012
With sed:
Code:
sed 's/^\(.\{149\}\)./\1X/' inputfile

This User Gave Thanks to elixir_sinari For This Post:
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Replace nth character in a file with a period

Hi all, If you look at the example below,I want to replace the 21st character (,) with a period (.). I have 1000 records in a file can someone help me how to do that. Thankyou all in advance. "2008-07-15... (3 Replies)
Discussion started by: blackhawk_123
3 Replies

2. Shell Programming and Scripting

Print lines with specific character at nth position in a file

I need to print lines with character S at nth position in a file...can someone pl help me with appropriate awk command for this (2 Replies)
Discussion started by: manaswinig
2 Replies

3. Shell Programming and Scripting

Print lines with specific character at nth position in a file

I need to print lines with character S at nth position in a file...can someone pl help me with appropriate awk command for this (1 Reply)
Discussion started by: manaswinig
1 Replies

4. UNIX for Dummies Questions & Answers

How to replace character on defined position

I need to replace the character on 6th position. If this character is 1 I have to repleace it with A, if it is 2 than I have to replace it with B. If it is not 1 or 2 I should not repleace it. input: abcd defg abcd 1efg mnop weac rstu 2bcd i need: abcd defg abcd Aefg mnop weac rstu... (2 Replies)
Discussion started by: necroman08
2 Replies

5. Shell Programming and Scripting

Replace character in certain position in a string

Hello everyone this is my first post of many to come :) I am writing a script and in this script at one point i need to replace a character in a particular position in a string for example: in the string "mystery" i would need to replace the 3rd position to an "r" so the string becomes... (3 Replies)
Discussion started by: snipaa
3 Replies

6. Shell Programming and Scripting

Find character and Replace character for given position

Hi, i want find the character '-' in a file from position 284-298, if it occurs i need to replace it with 'O ' for the position in the file. How to do that using SED command. thanks in advance, Sara (9 Replies)
Discussion started by: Sara183
9 Replies

7. Shell Programming and Scripting

To find nth position of character in string

Hi guyz i want to know nth position of character in string. For ex. var="UK,TK,HK,IND,AUS" now if we see 1st occurance of , is at 3 position, 2nd at 6,..4th at 13 position. 1st position we can find through INDEX, but what about 2nd,3rd and 4th or may be upto nth position. ? In oracle we had... (2 Replies)
Discussion started by: Jonty Immortal
2 Replies

8. Shell Programming and Scripting

awk script to replace nth character with comma

I have a requirement as below. In one of my column, I have data which may or may not be separted with coma always. Now I need to validate the length of these text within the coma (if available) and if the length is more than 30 characters, I need to insert a coma either at 30 characters if its... (3 Replies)
Discussion started by: aramacha
3 Replies

9. Shell Programming and Scripting

Replace nth to nth character?

Hi I got the following problem and I wonder if some could please help me out? I'd like to replace character 8 - 16 , 16 - 24 cat file ... (2 Replies)
Discussion started by: stinkefisch
2 Replies

10. Post Here to Contact Site Administrators and Moderators

Search for a pattern and replace a space at specific position with a Character in File

In file, we have millions of records each of 1000 in length. And at specific position say 800 there is a space, we need to replace it with Character X if the ID in that row starts with 123. So far i have used the below which is replacing space at that position to X but its not checking for... (3 Replies)
Discussion started by: Jagmeet Singh
3 Replies
sed(1)							      General Commands Manual							    sed(1)

Name
       sed - stream text editor

Syntax
       sed [-n] [-e script] [-f sfile] [file...]

Description
       The  command  copies  the  named  files	(standard input default) to the standard output, edited according to a script of commands.  The -f
       option causes the script to be taken from file sfile; these options accumulate.	If there is just one -e option and no -f's,  the  flag	-e
       may  be omitted.  The -n option suppresses the default output; inclusion in the script of a comment command of the form also suppresses the
       default output.	(See the description of the `#' command.)

       A script consists of editing commands of the following form:

	      [address [, address] ] function [arguments]

       Nominally, there is one command per line; but commands can be concatenated on a line by being separated with semicolons

       In normal operation cyclically copies a line of input into a pattern space (unless there is something left after a `D' command), applies in
       sequence all commands whose addresses select that pattern space, and at the end of the script copies the pattern space to the standard out-
       put (except under -n) and deletes the pattern space.

       An address is either a decimal number that counts input lines cumulatively across files, a `$' that addresses the last line of input, or  a
       context address, `/regular expression/', in the style of ed(1) modified thus:

	  o    In  a  context  address, the construction ?regular expression?, where ? is any character, is identical to regular expression. Note
	       that in the context address xabcxdefx, the second x stands for itself, so that the regular expression is abcxdef.

	  o    The escape sequence `
' matches a new line embedded in the pattern space.

	  o    A command line with no addresses selects every pattern space.

	  o    A command line with one address selects each pattern space that matches the address.

	  o    A command line with two addresses selects the inclusive range from the first pattern space that matches the first  address  through
	       the  next  pattern  space  that matches the second.  (If the second address is a number less than or equal to the line number first
	       selected, only one line is selected.)  Thereafter the process is repeated, looking again for the first address.

       Editing commands can be applied only to non-selected pattern spaces by use of the negation function `!' (below).

       In the following list of functions the maximum number of permissible addresses for each function is indicated in parentheses.

       An argument denoted text consists of one or more lines, all but the last of which end with `' to hide the new line.  Backslashes  in  text
       are  treated  like  backslashes in the replacement string of an `s' command, and may be used to protect initial blanks and tabs against the
       stripping that is done on every script line.

       An argument denoted rfile or wfile must terminate the command line and must be preceded by exactly one blank.  Each wfile is created before
       processing begins.  There can be at most 10 distinct wfile arguments.

       (1)a
       text
	       Append.	Place text on the output before reading the next input line.

       (2)b label
	       Branch to the `:' command bearing the label.  If label is empty, branch to the end of the script.

       (2)c
       text
	       Change.	 Delete  the  pattern space.  With 0 or 1 address or at the end of a 2-address range, place text on the output.  Start the
	       next cycle.

       (2)d    Delete the pattern space.  Start the next cycle.

       (2)D    Delete the initial segment of the pattern space through the first new line.  Start the next cycle.

       (2)g    Replace the contents of the pattern space by the contents of the hold space.

       (2)G    Append the contents of the hold space to the pattern space.

       (2)h    Replace the contents of the hold space by the contents of the pattern space.

       (2)H    Append the contents of the pattern space to the hold space.

       (1)i
       text
	       Insert.	Place text on the standard output.

       (2)n    Copy the pattern space to the standard output.  Replace the pattern space with the next line of input.

       (2)N    Append the next line of input to the pattern space with an embedded new line.  (The current line number changes.)

       (2)p    Print.  Copy the pattern space to the standard output.

       (2)P    Copy the initial segment of the pattern space through the first new line to the standard output.

       (1)q    Quit.  Branch to the end of the script.	Do not start a new cycle.

       (2)r rfile
	       Read the contents of rfile.  Place them on the output before reading the next input line.

       (2)s/regular expression/replacement/flags
	       Substitute the replacement string for instances of the regular expression in the pattern space.	Any character may be used  instead
	       of `/'.	For a more complete description see The flags is zero or more of

	       g       Global.	Substitute for all nonoverlapping instances of the regular expression rather than just the first one.

	       p       Print the pattern space if a replacement was made.

	       w wfile Write.  Append the pattern space to wfile if a replacement was made.

       (2)t label
	       Test.   Branch  to  the `:' command bearing the label if any substitutions have been made since the most recent reading of an input
	       line or execution of a `t'.  If label is empty, branch to the end of the script.

       (2)w wfile
	       Write.  Append the pattern space to wfile.

       (2)x    Exchange the contents of the pattern and hold spaces.

       (2)y/string1/string2/
	       Transform.  Replace all occurrences of characters in string1 with the corresponding character in string2.  The lengths  of  string1
	       and string2 must be equal.

       (2)! function
	       Don't.  Apply the function (or group, if function is `{') only to lines not selected by the address(es).

       (0): label
	       This command does nothing; it bears a label for `b' and `t' commands to branch to.

       (1)=    Place the current line number on the standard output as a line.

       (2){    Execute the following commands through a matching `}' only when the pattern space is selected.

       (0)     An empty command is ignored.

       (0)#    With one exception, any line whose first nonblank character is a number sign is a comment and is ignored.  The exception is that if
	       the first such line encountered contains only the number sign followed by the letter `n' the default output is suppressed as if the
	       -n option were in force.

Options
       -e 'command;command...'
	       Uses command;command...	as the editing script.	If no -f option is given, the -e keyword can be omitted.  For example, the follow-
	       ing two command are functionally identical:
	       % sed -e 's/DIGITAL/Digital/g' summary > summary.out
	       % sed 's/DIGITAL/Digital/g' summary > summary.out

       -f sfile
	       Uses specified file as input file of commands to be executed.  Can be used with -e option to apply both	explicit  commands  and  a
	       separate script file.

       -n      Suppresses  all	normal	output, writing only lines explicitly written by the `p' or `P' commands or by an `s' command with the `p'
	       flag.

See Also
       awk(1), ed(1), grep(1), lex(1)

																	    sed(1)
All times are GMT -4. The time now is 04:00 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy