Sponsored Content
Top Forums UNIX for Beginners Questions & Answers How to use cat grep and cut together? Post 303044564 by synack on Wednesday 26th of February 2020 12:56:31 PM
Old 02-26-2020
Quote:
Originally Posted by RudiC
There's NO string like "reached" in your samples, nor semicolons. Those don't show up in my host calls, either. Replace ! /^Host/ with /domain/ or /name/ or /pointer/. If that doesn't help, show your input data.


cat is by no means needed in any of your attempts as both grep and cut can open files by themselves, or you can redirect stdin for them.
grepping the first number is quite easy, like

Code:
$ host 82.165.230.17 | grep -o "^[^.]*"
17

, but extracting the remote hostname not so as you don't know what the FQDN looks like. The nearest I get is

Code:
$ host 82.165.230.17 | grep -oE "^[^.]*| [^. ]*\."
17
 bap.

Yes you are right. it's my fault. There somes lines that i didn't see in the original file, like ";; connection timed out; no servers could be reached"


thank you for your explanation and your help.
 

10 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

cat and grep not working

I am trying to cat a file and then grep that file for a number. I can do it fine on other files but this particular file will not do anything. I tried running it on an older file from the same device but it is just not working. The file is nothing more than a flat file on a unix box. Here is just a... (3 Replies)
Discussion started by: jphess
3 Replies

2. UNIX for Dummies Questions & Answers

cat, grep and tee to a local file

Hi, This is what I am trying to do. 1) connect to 3 remote servers from my local machine serverA serverB serverC 2) read error file from each server cat /var/lib/mysql/mydb.err 3) grep for lines displaying "yesterday" date grep "`date +%y%m%d' '-d\"1 day ago\"`" 4) Append those lines to a... (7 Replies)
Discussion started by: shantanuo
7 Replies

3. Shell Programming and Scripting

cat or cut to delimit csv?

Hi, Im a pretty large noob to linux/perl etc and im trying to use mysql slurp to take a delimited file and import it into mysql using stdin (in the hope its faster) mysqlslurp - slurp <STDIN> into a MySQL table - search.cpan.org Christopher Brown / MySQL-Slurp - search.cpan.org Using... (3 Replies)
Discussion started by: newtony
3 Replies

4. Shell Programming and Scripting

cat /etc/passwd and grep -v on /etc/shells

Hi All, I'd like to do this cat /etc/passwd and grep -v on the /etc/shells list I'd like to find all shell that doesn't exist on the /etc/passwd. Is there an easy way without doing a egrep -v "/bin/sh|/bin/bash................"? How do I use a file /etc/shells as my list for... (4 Replies)
Discussion started by: itik
4 Replies

5. Shell Programming and Scripting

cat -n and grep

I am not sure if using cat -n is the most efficient way to split a file into multiple files, one file per line in the source file. I thought using cat -n would make it easy to process the file because it produces an output that numbers each line that I could then grep for with the regex "^ *$i".... (3 Replies)
Discussion started by: kapu
3 Replies

6. Shell Programming and Scripting

grep or cat using sed

Is there a way using grep or cat a file to create a new file based on whether the first 9 positions of each record is less than 399999999? This is a fixed file format. (3 Replies)
Discussion started by: ski
3 Replies

7. Slackware

How should I cut this line using cut and grep?

not sure how to do it. wan't to delete it using cut and grep ince i would use it in the shell. but how must the command be? grep "64.233.181.103 wwwGoogle.com" /etc/hosts | cut -d the delimeter is just a space. can you help meplease. :D (1 Reply)
Discussion started by: garfish
1 Replies

8. UNIX for Dummies Questions & Answers

Grep and cat combined

Hello, i need to search one word (snp1) from many files and copy the content of the columns of this word in new file. example: file 1: SNP BP CHR P snp1 1 3 0.01 snp2 2 2 0.05 . . file 2: SNP BP CHR P snp1 1 3 0.06 snp2 2 2 0.3 output... (6 Replies)
Discussion started by: biopsy
6 Replies

9. Shell Programming and Scripting

Replace cat and grep with <

Hello someone told me to use OS=`awk '{print int($3)}' < /etc/redhat-release` instead of OS=cat /etc/redhat-release | `awk '{print int($3)}'` any idea for the reason ? (5 Replies)
Discussion started by: nimafire
5 Replies

10. UNIX for Dummies Questions & Answers

Grep or cat The Whole Directory PROBLEMS :(

Hi Guys This is my first post so I am not sure how things go here. I'm sorry if I'm breaking the rule or something. Feel free to correct me about that :) So as I was saying... I'd been trying to grep this folder containing 900,000 txt files but seems no luck. I get either "No such file... (6 Replies)
Discussion started by: Nexeu
6 Replies
cut(1)							      General Commands Manual							    cut(1)

Name
       cut - cut out selected fields of each line of a file

Syntax
       cut -clist [file1 file2...]
       cut -flist [-dchar] [-s] [file1 file2...]

Description
       Use  the  command to cut out columns from a table or fields from each line of a file.  The fields as specified by list can be fixed length,
       that is, character positions as on a punched card (-c option), or the length can vary from line to line and be marked with a  field  delim-
       iter character like tab (-f option).  The command can be used as a filter.  If no files are given, the standard input is used.

       Use to make horizontal ``cuts'' (by context) through a file, or to put files together in columns.  To reorder columns in a table, use and

Options
       list	   Specifies  ranges  that must be a comma-separated list of integer field numbers in increasing order.  With optional - indicates
		   ranges as in the -o option of nroff/troff for page ranges; for example, 1,4,7; 1-3,8; -5,10 (short for 1-5,10);  or	3-  (short
		   for third through last field).

       -clist	   Specifies character positions to be cut out.  For example, -c1-72 would pass the first 72 characters of each line.

       -flist	   Specifies  the  fields  to be cut out.  For example, -f1,7 copies the first and seventh field only.	Lines with no field delim-
		   iters are passed through intact (useful for table subheadings), unless -s is specified.

       -dchar	   Uses the specified character as the field delimiter.  Default is tab.  Space or other characters with special  meaning  to  the
		   shell must be quoted.  The -d option is used only in combination with the -f option, according to XPG3 and SVID2/SVID3.

       -s	   Suppresses  lines  with  no	delimiter  characters.	 Unless  specified, lines with no delimiters are passed through untouched.
		   Either the -c or -f option must be specified.

Examples
       Mapping of user IDs to names:
       cut -d: -f1,5 /etc/passwd
       To set name to the current login name for the csh shell:
       set name=`who am i | cut -f1 -d" "`
       To set name to the current login name for the sh, sh5, and ksh shells:
       name=`who am i | cut -f1 -d" "`

Diagnostics
       "line too long"	   A line can have no more than 511 characters or fields.

       "bad list for c/f option"
			   Missing -c or -f option or incorrectly specified list.  No error occurs if a line has fewer fields than the list  calls
			   for.

       "no fields"	   The list is empty.

See Also
       grep(1), paste(1)

																	    cut(1)
All times are GMT -4. The time now is 04:18 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy