Sponsored Content
Homework and Emergencies Homework & Coursework Questions Shell Script to read a tab delimited file and perform simple tasks Post 302745481 by jsmith6932 on Monday 17th of December 2012 10:27:03 AM
Old 12-17-2012
Quote:
Originally Posted by jim mcnamara
IFS is used to tell the shell what the field separator character is. \n is normally the record separator. The file has tab characters to separate the fields - how do you write a tab?

Are you allowed to use awk?
From what I got 'IFS=$'\n' is the way of telling the shell that the file being read is tab delimited.

Yes I was going to use the awk command to parse and separate the file. We are allowed to use any command that is in the bash shell.
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Converting Tab delimited file to Comma delimited file in Unix

Hi, Can anyone let me know on how to convert a Tab delimited file to Comma delimited file in Unix Thanks!! (22 Replies)
Discussion started by: charan81
22 Replies

2. UNIX for Dummies Questions & Answers

Read a tab delimited

OK, let's set this up. I have a tab delimited file from excel. In my UNIX shell I have the following lines IFS=`printf "\t"` while read LINE_NO SKIP IGNORE_ERRORS OTHER do .... This works fine if there is something in every column like this. NOTE, those are tabs, not spaces. :) ... (2 Replies)
Discussion started by: podzach
2 Replies

3. Shell Programming and Scripting

Retrieving values from tab-delimited file in unix script

Hi I am trying to retrieve values from a tab-delimited file.I am using while read record value=`echo $record | cut -f12` done Where 12 is the column no i want retieve and record is one line of the file. But it is returning the full record. Plz help (4 Replies)
Discussion started by: akashtcs
4 Replies

4. Shell Programming and Scripting

Mac script - issue with tab delimited input file

Hi: I'm writing a script that will take source / destination pathnames and metadata information from a tab-delimited input file, and then perform various directory creation, file moving and renaming, and tagging of files. I think I have what I need to do the file manipulation in the script -... (4 Replies)
Discussion started by: GRIMESPACE
4 Replies

5. UNIX for Dummies Questions & Answers

tab delimited file that is not tab delimited.

Hi Forum I have a tab delimited file that opens well in Openoffice calc (excel). But when I perform any operation in command line, it reads the file incorrectly. When I 'save As' the same file in office as tab delimited then it works fine. The file that I think is tab delimited is actually... (8 Replies)
Discussion started by: imlearning
8 Replies

6. Shell Programming and Scripting

Help with converting Pipe delimited file to Tab Delimited

I have a file which was pipe delimited, I need to make it tab delimited. I tried with sed but no use cat file | sed 's/|//t/g' The above command substituted "/t" not tab in the place of pipe. Sample file: abc|123|2012-01-30|2012-04-28|xyz have to convert to: abc 123... (6 Replies)
Discussion started by: karumudi7
6 Replies

7. Shell Programming and Scripting

How to make tab delimited file to space delimited?

Hi How to make tab delimited file to space delimited? in put file: ABC kgy jkh ghj ash kjl o/p file: ABC kgy jkh ghj ash kjl Use code tags, thanks. (1 Reply)
Discussion started by: jagdishrout
1 Replies

8. Shell Programming and Scripting

How to read data from tab delimited file after a specific position?

Hi Experts, I have a tab deliminated file as below myfile.txt Local Group Memberships *Administrators *Guests I need data in below format starting from 4th position. myfile1.txt Administrators Guests the above one is just an example and there could... (15 Replies)
Discussion started by: Litu1988
15 Replies

9. UNIX for Dummies Questions & Answers

Need to convert a pipe delimited text file to tab delimited

Hi, I have a rquirement in unix as below . I have a text file with me seperated by | symbol and i need to generate a excel file through unix commands/script so that each value will go to each column. ex: Input Text file: 1|A|apple 2|B|bottle excel file to be generated as output as... (9 Replies)
Discussion started by: raja kakitapall
9 Replies

10. UNIX for Beginners Questions & Answers

Replace a column in tab delimited file with column in other tab delimited file,based on match

Hello Everyone.. I want to replace the retail col from FileI with cstp1 col from FileP if the strpno matches in both files FileP.txt ... (2 Replies)
Discussion started by: YogeshG
2 Replies
read(1) 							   User Commands							   read(1)

NAME
read - read a line from standard input SYNOPSIS
/usr/bin/read [-r] var... sh read name... csh set variable = $< ksh read [ -prsu [n]] [ name ? prompt] [name...] DESCRIPTION
/usr/bin/read The read utility will read a single line from standard input. By default, unless the -r option is specified, backslash () acts as an escape character. If standard input is a terminal device and the invoking shell is interactive, read will prompt for a continuation line when: o The shell reads an input line ending with a backslash, unless the -r option is specified. o A here-document is not terminated after a NEWLINE character is entered. The line will be split into fields as in the shell. The first field will be assigned to the first variable var, the second field to the second variable var, and so forth. If there are fewer var operands specified than there are fields, the leftover fields and their interven- ing separators will be assigned to the last var. If there are fewer fields than vars, the remaining vars will be set to empty strings. The setting of variables specified by the var operands will affect the current shell execution environment. If it is called in a subshell or separate utility execution environment, such as one of the following: (read foo) nohup read ... find . -exec read ... ; it will not affect the shell variables in the caller's environment. The standard input must be a text file. sh One line is read from the standard input and, using the internal field separator, IFS (normally space or tab), to delimit word boundaries, the first word is assigned to the first name, the second word to the second name, and so on, with leftover words assigned to the last name. Lines can be continued using ewline. Characters other than NEWLINE can be quoted by preceding them with a backslash. These backslashes are removed before words are assigned to names, and no interpretation is done on the character that follows the backslash. The return code is 0, unless an end-of-file is encountered. csh The notation: set variable = $< loads one line of standard input as the value for variable. (See csh(1)). ksh The shell input mechanism. One line is read and is broken up into fields using the characters in IFS as separators. The escape character, (), is used to remove any special meaning for the next character and for line continuation. In raw mode, -r, the character is not treated specially. The first field is assigned to the first name, the second field to the second name, and so on, with leftover fields assigned to the last name. The -p option causes the input line to be taken from the input pipe of a process spawned by the shell using |&. If the -s flag is present, the input will be saved as a command in the history file. The flag -u can be used to specify a one digit file descriptor unit n to read from. The file descriptor can be opened with the exec special command. The default value of n is 0. If name is omitted, REPLY is used as the default name. The exit status is 0 unless the input file is not open for reading or an end-of-file is encoun- tered. An end-of-file with the -p option causes cleanup for this process so that another can be spawned. If the first argument contains a ?, the remainder of this word is used as a prompt on standard error when the shell is interactive. The exit status is 0 unless an end-of- file is encountered. OPTIONS
The following option is supported: -r Does not treat a backslash character in any special way. Considers each backslash to be part of the input line. OPERANDS
The following operand is supported: var The name of an existing or non-existing shell variable. EXAMPLES
Example 1: An example of the read command The following example for /usr/bin/read prints a file with the first field of each line moved to the end of the line: example% while read -r xx yy do printf "%s %s " "$yy" "$xx" done < input_file ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables that affect the execution of read: LANG, LC_ALL, LC_CTYPE, LC_MES- SAGES, and NLSPATH. IFS Determines the internal field separators used to delimit fields. PS2 Provides the prompt string that an interactive shell will write to standard error when a line ending with a backslash is read and the -r option was not specified, or if a here-document is not terminated after a newline character is entered. EXIT STATUS
The following exit values are returned: 0 Successful completion. >0 End-of-file was detected or an error occurred. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), ksh(1), line(1), set(1), sh(1), attributes(5), environ(5), standards(5) SunOS 5.10 28 Mar 1995 read(1)
All times are GMT -4. The time now is 02:55 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy