Linux in a Nutshell, Fifth Edition

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Chapter 6: The Bash Shell and Korn Shell

This is the Title of the Book, eMatter Edition

Copyright © 2006 O’Reilly & Associates, Inc. All rights reserved.

-n Suppress command numbering from the -l listing.

-r Reverse the order of the -l listing.

-s Equivalent to -e -. Not in ksh88.

fc

fc

ksh93 alias for hist.

fg

fg [jobIDs]

Bring current job or jobIDs to the foreground. See the earlier

section “Job Control.”

fi

fi

Reserved word that ends an if statement. (Don’t forget to use it!)

for

for x [in list]

do

commands

done

For variable x (in optional list of values) do commands.Ifin list is

omitted, "$@" (the positional parameters) is assumed.

Examples

Paginate files specified on the command line; save each result:

for file; do

pr $file > $file.tmp

done

Search chapters for a list of words (like fgrep -f):

for item in `cat program_list`

do

echo "Checking chapters for"

echo "references to program $item..."

grep -c "$item.[co]" chap*

done

Extract a one-word title from each file and use as new filename:

for file

do

name=`sed -n 's/NAME: //p' $file`

mv $file $name

done

for

for ((init; cond; incr))

do

commands

done

Bash and ksh93. Arithmetic for loop, similar to C’s. Evaluate init.

While cond is true, execute the body of the loop. Evaluate incr