Operation Manual
${VAR#pattern}
removes the shortest possible match from the left:
file=/home/tux/book/book.tar.bz2
echo ${file#*/}
home/tux/book/book.tar.bz2
${VAR##pattern}
removes the longest possible match from the left:
file=/home/tux/book/book.tar.bz2
echo ${file##*/}
book.tar.bz2
${VAR%pattern}
removes the shortest possible match from the right:
file=/home/tux/book/book.tar.bz2
echo ${file%.*}
/home/tux/book/book.tar
${VAR%%pattern}
removes the longest possible match from the right:
file=/home/tux/book/book.tar.bz2
echo ${file%%.*}
/home/tux/book/book
${VAR/pattern_1/pattern_2}
substitutes the content of VAR from the pattern_1 with pattern_2:
file=/home/tux/book/book.tar.bz2
echo ${file/tux/wilber}
/home/wilber/book/book.tar.bz2
20.6 Grouping And Combining
Commands
Shells allow you to concatenate and group commands for conditional execution. Each
command returns an exit code which determines the success or failure of its operation.
If it is 0 (zero) the command was successful, everything else marks an error which is
specic to the command.
The following list shows, how commands can be grouped:
304 Reference