Sponsored Content
Top Forums Shell Programming and Scripting Grepping for hex characters - explanation? Post 302491084 by mregine on Wednesday 26th of January 2011 04:49:23 PM
Old 01-26-2011
Grepping for hex characters - explanation?

Hello,

Yesterday I was looking for a way to grep for a tab in the shell, and found this solution in several places:
Code:
grep $'[\x09]a[\x09]' # Grep for the letter 'a' between two tabs

I'm fine with most of this, but I don't understand what the $ (dollar sign) before the first quote does. It doesn't work without, but I couldn't find any explanation in the grep man or info pages. The only mention of $ there is as a meta-character that matches the end of a regular expression.

Can someone explain and/or point me to other documentation where I can read it up?

Thanks!
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

grepping the first 3 characters from a file

Hi I was wondering if it's possible to use a command to get the first 3 characters of a line in a text file, I tried grep but it returns the whole line but I am only interested in the first 3 characters. Is this possible with grep or I need any other command? Also is it possible deleting from... (2 Replies)
Discussion started by: g-e-n-o
2 Replies

2. UNIX for Dummies Questions & Answers

grepping the first 3 characters from a file

give this a try and let me know if it works grep '^' filename rachael (2 Replies)
Discussion started by: rachael
2 Replies

3. Shell Programming and Scripting

Replacing all but last Hex characters in a text line

I must remove hex characters 0A and 0D from several fields within an MS Access Table. Since I don't think it can be done in Access, I am trying here. I am exporting a Table from Access (must be fixed length fields, I think, for my idea to work here) into a text format. I then want to run a... (2 Replies)
Discussion started by: BAH
2 Replies

4. HP-UX

Hex characters of ascii file

Hi, Whats the command or how do you display the hexadecimal characters of an ascii file. thanks Bud (2 Replies)
Discussion started by: budrito
2 Replies

5. Shell Programming and Scripting

Grepping characters

Hi friends, I want your help. I have a flat file. I want a script to search following pattern in it and once it get that pattern it should grep next 7 characters from it and should keep it in output file output.TXT Pattern is RSTD3R0******* In above example, characters in the place of *... (3 Replies)
Discussion started by: anushree.a
3 Replies

6. Programming

After converting the hexstr to Hex and storing the Hex in a char*

Hi All, My main intension of is to convert the Hexstring stored in a char* into hex and then prefixing it with "0x" and suffix it with ',' This has to be done for all the hexstring char* is NULL. Store the result prefixed with "0x" and suffixed with ',' in another char* and pass it to... (1 Reply)
Discussion started by: rvan
1 Replies

7. Shell Programming and Scripting

Replacing hex characters '\x0D' with '\x0D\x0A'

Hello All, I have a requirement where I need to replaced the hex character - '\x0D' with 2 hex characters - 'x0D' & 'x0A' I am trying to use SED - But somehow its not working. Any pointers? Also the hex character '\x0D' can occur anywhere in the line. Can this also be accomplished... (6 Replies)
Discussion started by: paragkalra
6 Replies

8. Shell Programming and Scripting

Convert hex values to displayable characters

Hi, I am a bit stuck with displaying characters. I am having values like below in the proper displayable characters. which I would want to print the actual value on the right hand side. I dont want to create an array because I would have to create 255 different values. isnt there another way of... (17 Replies)
Discussion started by: ahmedwaseem2000
17 Replies

9. UNIX for Dummies Questions & Answers

Replacing hex characters

I have the following file consisting of dates and sample measurements: 05��Oct��2010 1.31�� 06��Oct��2010 1.32�� 07��Oct��2010 1.31�� The hex characters are \xc2\xa0 in sequence. I have tried to remove the characters as follows: sed -i '' -e 's/\xc2\xa0//g' file.dat and as follows... (6 Replies)
Discussion started by: figaro
6 Replies

10. HP-UX

Replacing Hex Characters In A File Using awk?

Hi guys, First off, i'm a complete noob to UNIX and LINUX so apologies if I don't understand the basics! I have a file which contains a hex value of '0D' at the end of each line when I look at it in a hex viewer. I need to change it so it contains a hex value of '0D0A0A' I thought... (10 Replies)
Discussion started by: AndyBSG
10 Replies
TABS(1) 						    BSD General Commands Manual 						   TABS(1)

NAME
tabs -- set terminal tabs SYNOPSIS
tabs [-n | -a | -a2 | -c | -c2 | -c3 | -f | -p | -s | -u] [+m[n]] [-T type] tabs [-T type] [+[n]] n1[,n2,...] DESCRIPTION
The tabs utility displays a series of characters that clear the hardware terminal tab settings then initialises tab stops at specified posi- tions, and optionally adjusts the margin. In the first synopsis form, the tab stops set depend on the command line options used, and may be one of the predefined formats or at regular intervals. In the second synopsis form, tab stops are set at positions n1, n2, etc. If a position is preceded by a '+', it is relative to the previous position set. No more than 20 positions may be specified. If no tab stops are specified, the ``standard'' UNIX tab width of 8 is used. The options are as follows: -n Set a tab stop every n columns. If n is 0, the tab stops are cleared but no new ones are set. -a Assembler format (columns 1, 10, 16, 36, 72). -a2 Assembler format (columns 1, 10, 16, 40, 72). -c COBOL normal format (columns 1, 8, 12, 16, 20, 55) -c2 COBOL compact format (columns 1, 6, 10, 14, 49) -c3 COBOL compact format (columns 1, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62, 67). -f FORTRAN format (columns 1, 7, 11, 15, 19, 23). -p PL/1 format (columns 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61). -s SNOBOL format (columns 1, 10, 55). -u Assembler format (columns 1, 12, 20, 44). +m[n], +[n] Set an n character left margin, or 10 if n is omitted. -T type Output escape sequence for the terminal type type. ENVIRONMENT
The LANG, LC_ALL, LC_CTYPE and TERM environment variables affect the execution of tabs as described in environ(7). The -T option overrides the setting of the TERM environment variable. If neither TERM nor the -T option are present, tabs will fail. EXIT STATUS
The tabs utility exits 0 on success, and >0 if an error occurs. SEE ALSO
expand(1), stty(1), tput(1), unexpand(1), termcap(5) STANDARDS
The tabs utility conforms to IEEE Std 1003.1-2001 (``POSIX.1''). HISTORY
A tabs utility appeared in PWB UNIX. This implementation was introduced in FreeBSD 5.0. BUGS
The current termcap(5) database does not define the 'ML' (set left soft margin) capability for any terminals. BSD
May 20, 2002 BSD
All times are GMT -4. The time now is 07:15 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy