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Top Forums Shell Programming and Scripting Grabbing fields without using external commands Post 303008141 by Scott on Monday 27th of November 2017 06:00:12 PM
Old 11-27-2017
If you change the read to read into an array, you can access each member of the array by index.
e.g.
Code:
unset line
while IFS=_ read -A line; do
  NF=$((${#line[@]}-1))
  echo ${line[(($NF))]} # last field
  echo ${line[(($NF-1))]} # second last field
done < file

You could combine those two echo lines inside the while-loop with:
Code:
echo ${line[((${#line[@]}-1))]} # last field
echo ${line[((${#line[@]}-2))]} # second last field

but it's a bit messier to look at.

edit: I guess that's read -a (lowercase -a in Bash)

edit 2: Another option, using shell positional parameters:
Code:
while read line; do
 IFS=_ set -- $line
 ...
done < file


Last edited by Scott; 11-27-2017 at 07:16 PM.. Reason: edit
This User Gave Thanks to Scott For This Post:
 

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line(1) 						      General Commands Manual							   line(1)

NAME
line - Reads one line from standard input SYNOPSIS
line STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: line: XCU5.0 Refer to the standards(5) reference page for more information about industry standards and associated tags. OPTIONS
None DESCRIPTION
The line command copies one line, up to and including a newline, from standard input and writes it to standard output. Use this command within a shell command file to read from your terminal. The line command always writes at least a newline character. NOTES
The line utility has no internationalization features and is marked LEGACY in XCU Issue 5. Use the read utility instead. EXIT STATUS
Success. End-of-File. EXAMPLES
To read a line from the keyboard and append it to a file, enter: echo 'Enter comments for the log:' echo ': c' line >>log This shell procedure displays the message: Enter comments for the log: It then reads a line of text from the keyboard and adds it to the end of the file log. The echo ': c' command displays a : (colon) prompt. See the echo command for information about the c escape sequence. SEE ALSO
Commands: echo(1), ksh(1), read(1), Bourne shell sh(1b), POSIX shell sh(1p) Functions: read(2) Standards: standards(5) line(1)
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