Basic Linux filesystem commands

Quick reference for some basic filesystem commands:

cd	Go back to user directory
rm –f –r directoryname	Delete folder with all files and subdirs without prompt
cp filename newname	Copy filename to the new filename
mv filename newname	Move or rename file
Ls -ltrA	List all files:  "-A" including hidden dot files, but not the current or parent directory "." and ".."  "-t" and "-r" sort by modification time; in reverse order (oldest first)  "-l" as a list (one file per line, including size, date, permissions)
chmod <550> <file> <file>	Change chmod....
stat --format '%a' filename	List chmod for the filename
df	Show directory space usage
du –m  ls -l --block-size=MB	Show files and size
find . -type f -size +100M -exec ls -lh {} \;	List files bigger than 100MB
find . -type f -size +100M -exec gzip "{}" \;	Gzip all files over 100M under current path (incl. Subdirs)
find / -name *sometext* 2> /dev/null	Find files (from root "/") with sometext in the name, suppressing errors (redirecting error output to null)
find / -type f -iname cmp_rule_*.dat 2>/dev/null	Find (from /) ; files only (-type f) ; with case insensitive name (-iname) cmp_rule_<anything>.dat ; redirect stderr to null
mv `find . -maxdepth 1 -mtime +90` archive/	Move all files in the current folder (not recursive "-maxdepth 1") that were modified more than 90 days ago "-mtime +90" to the archive subfolder