Advanced Bash−Scripting Guide

Advanced Bash−Scripting Guide
#!/bin/bash
# Delete filenames in current directory containing bad characters.
for filename in *
do
badname=`echo "$filename" | sed −n /[\+\{\;\"\\\=\?~\(\)\\&\*\|\$]/p`
# Files containing those nasties: + { ; " \ = ? ~ ( ) < > & * | $
rm $badname 2>/dev/null # So error messages deep−sixed.
done
# Now, take care of files containing all manner of whitespace.
find . −name "* *" −exec rm −f {} \;
# The path name of the file that "find" finds replaces the "{}".
# The '\' ensures that the ';' is interpreted literally, as end of command.
exit 0
#−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
# Commands below this line will not execute because of "exit" command.
# An alternative to the above script:
find . −name '*[+{;"\\=?~()&*|$ ]*' −exec rm −f '{}' \;
exit 0
# (Thanks, S.C.)
Example 12−3. Deleting a file by its inode number
#!/bin/bash
# idelete.sh: Deleting a file by its inode number.
# This is useful when a filename starts with an illegal character,
#+ such as ? or −.
ARGCOUNT=1
E_WRONGARGS=70
E_FILE_NOT_EXIST=71
E_CHANGED_MIND=72
# Filename arg must be passed to script.
if [ $# −ne "$ARGCOUNT" ]
then
echo "Usage: `basename $0` filename"
exit $E_WRONGARGS
fi
if [ ! −e "$1" ]
then
echo "File \""$1"\" does not exist."
exit $E_FILE_NOT_EXIST
fi
inum=`ls −i | grep "$1" | awk '{print $1}'`
# inum = inode (index node) number of file
# Every file has an inode, a record that hold its physical address info.
echo; echo −n "Are you absolutely sure you want to delete \"$1\" (y/n)? "
# The '−v' option to 'rm' also asks this.
read answer
case "$answer" in
[nN]) echo "Changed your mind, huh?"
Chapter 12. External Filters, Programs and Commands 152