Advanced Bash−Scripting Guide

Advanced Bash−Scripting Guide
12.2. Complex Commands
Commands for more advanced users
find
−exec COMMAND \;
Carries out COMMAND on each file that find matches. The command sequence terminates with \; (the
";" is escaped to make certain the shell passes it to find literally). If COMMAND contains {}, then find
substitutes the full path name of the selected file for "{}".
bash$ find ~/ −name '*.txt'
/home/bozo/.kde/share/apps/karm/karmdata.txt
/home/bozo/misc/irmeyc.txt
/home/bozo/test−scripts/1.txt
find /home/bozo/projects −mtime 1
# Lists all files in /home/bozo/projects directory tree
#+ that were modified within the last day.
#
# mtime = last modification time of the target file
# ctime = last status change time (via 'chmod' or otherwise)
# atime = last access time
DIR=/home/bozo/junk_files
find "$DIR" −type f −atime +5 −exec rm {} \;
# Deletes all files in "/home/bozo/junk_files"
#+ that have not been accessed in at least 5 days.
#
# "−type filetype", where
# f = regular file
# d = directory, etc.
# (The 'find' manpage has a complete listing.)
find /etc −exec grep '[0−9][0−9]*[.][0−9][0−9]*[.][0−9][0−9]*[.][0−9][0−9]*' {} \;
# Finds all IP addresses (xxx.xxx.xxx.xxx) in /etc directory files.
# There a few extraneous hits − how can they be filtered out?
# Perhaps by:
find /etc −type f −exec cat '{}' \; | tr −c '.[:digit:]' '\n' \
| grep '^[^.][^.]*\.[^.][^.]*\.[^.][^.]*\.[^.][^.]*$'
# [:digit:] is one of the character classes
# introduced with the POSIX 1003.2 standard.
# Thanks, S.C.
The −exec option to find should not be confused with the exec shell builtin.
Example 12−2. Badname, eliminate file names in current directory containing bad characters
and whitespace.
Chapter 12. External Filters, Programs and Commands 151