Using Wildcards in bash for various file related task like list, rm.

bash-tricks-find.sh

# How To Use Find and Locate to Search for Files on a Linux
$ find -name "name_of_file_or_dir"      #Finding by Name
$ find -iname "name_of_file_or_dir"     #To find a file by name, but ignore the case of the name_of_file_or_dir

# Finding by Type
$ find -type type_descriptor query
#Some of the most common descriptors that you can use to specify the type of file are here:
#f: regular file
#d: directory
#l: symbolic link
#c: character devices
#b: block devices
$ find / -type f -name "*.conf"         #search for all files that end in ".conf" 

# Filtering by Time and Size
#c: bytes
#k: Kilobytes
#M: Megabytes
#G: Gigabytes
#b: 512-byte blocks
$ find / -size 50c        #find all files that are exactly 50 bytes
$ find / -size -50c         #find all files less than 50 bytes
$ find / -size +700M        #Find all files more than 700 Megabytes

#Time
#Linux stores time data about access times, modification times, and change times.
#Access Time: Last time a file was read or written to.
#Modification Time: Last time the contents of the file were modified.
#Change Time: Last time the file's inode meta-data was changed.
#We can use these with the "-atime", "-mtime", and "-ctime" parameters
$ find / -mtime 1   #find files that have a modification time of a day ago
$ find / -atime -1  #files that were accessed in less than a day ago
$ find / -ctime +3  #files that last had their meta information changed more than 3 days ago
$ find / -mmin -1   #companion parameters we can use to specify minutes instead of days
$ find / -newer myfile #files that have been modified type the system in the last minute

#Finding by Owner and Permissions
#You can also search for files by the file owner or group owner.
#You do this by using the "-user" and "-group" parameters respectively
$ find / -user syslog  #Find a file that is owned by the "syslog" user by entering
$ find / -group shadow #Find files owned by the "shadow" group by typing
$ find / -perm 644     #match an exact set of permissions, we use this form


#Executing and Combining Find Commands
#You can execute an arbitrary helper command on everything that find matches by using the "-exec" parameter. 
$ find find_parameters -exec command_and_params {} \; #The "{}" is used as a placeholder for the files that find matches. The "\;" is used so that find knows where the command ends.

# For instance, we could find the files in the previous section that had "644" permissions and modify them to have "664" permissions:
$ cd ~/test
$ find . -type f -perm 644 -exec chmod 664 {} \;

#We could then change the directory permissions like this:
$ find . -type d -perm 755 -exec chmod 700 {} \;
#If you want to chain different results together, you can use the "-and" or "-or" commands. The "-and" is assumed if omitted.
$ find . -name file1 -or -name file9 

bash-tricks.sh

$ ls *.jpg         # List all JPEG files
$ ls ?.jpg         # List JPEG files with 1 char names (eg a.jpg, 1.jpg)
$ rm [A-Z]*.jpg    # Remove JPEG files that start with a capital letter

$ shopt -s extglob
#Extended globbing as described by the bash man page:
# ?(pattern-list)   Matches zero or one occurrence of the given patterns
# *(pattern-list)   Matches zero or more occurrences of the given patterns
# +(pattern-list)   Matches one or more occurrences of the given patterns
# @(pattern-list)   Matches one of the given patterns
# !(pattern-list)   Matches anything except one of the given patterns

#pattern-list is a list of items separated by a vertical bar "|" (aka the pipe symbol)
#Bash              Regular Expression
# ?(pattern-list)   (...|...)?
# *(pattern-list)   (...|...)*
# +(pattern-list)   (...|...)+
# @(pattern-list)   (...|...)    [@ not a RE syntax]
# !(pattern-list)   "!" used as for negative assertions in RE syntax

# To list all the files that match the regular expression "ab(2|3)+.jpg" you could do:
$ ls ab+(2|3).jpg
#Now that's something you can't do with regular globbing. 
#Note: this matches files like ab2.jpg, ab3.jpg, ab2222.jpg, ab333.jpg, etc.

#This:
ls -alt [a-z]*.{jpg,gif}
# lists jpg/gif files that start with any lower case letter followed by any number of other characters.

#This:
ls -alt [a-z]?.{jpg,gif}
#lists jpg/gif files start with any lower case letter followed by any single character.

#This:
ls -alt t{[0-9]*,[a-z]*}.{jpg,gif}
#lists jpg/gif files that start with the letter t followed by either a digit or a lower case letter 
#and then followed by any number of other characters.