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File commands

File Commands
cat filename displays the contents of filename
cat filename(s) > newfile copies one or more files to a newly created newfile
cat filename >> destination appends the contents of filename to destination
chattr changes the file attributes of filename (see lsattr)
chmod permission
changes file permissions; (u) user's, (g) group's, (o) others'
rights can be (+) added or (-) deleted in (r) read, (w) write or
(x) execute mode. chmod u+x file adds execute rights to user.
chown : file changes ownership of file to and
cp oldfilename newfilename copies oldfilename to newfilename
file filename displays what type of file filename is
find / -name “filenamesearches entire root directory for filename
grep string filename searches for and displays the string within filename
gunzip filename uncompresses filename (if compressed with gzip)
gzip filename compresses filename (use gunzip to uncompress)
head filename displays the first ten lines of filename
less filename displays the contents of filename with the ability to scroll
ln –s source target creates a soft link from source to target (i.e. a shortcut)
locate filename searches for and locates filename (commands AND files)
NOTE: need to update db with root command “updatedb
lsof lists currently open files
more filename displays the contents of filename one screen at a time
mv oldfilename newfilename renames oldfilename to newfilename
mv filename directoryname moves filename to directoryname
rm filename removes or deletes filename
rpm –Uvh package-name
installs package-name (upgrades if package already
Add “--test” to test for dependencies before install.
sort filename alphabetizes (sorts) filename
split –b1m file files. splits file into multiple files.[x] files that are 1 MB each.
use cat to re-assemble (ex: cat* >
stat filename provides statistics on filename (like windows file properties)
tail filename displays the last ten lines of filename. –f to show new output
tar -cvf newfile.tar
packs fileordirectory and call the package newfile.tar.
(tar -xvf newfile.tar with will unpack the file)
touch file changes file timestamp of file (can also create file)
tree shows the directory tree of the current directory
vi a (brutal) text editor. Use nano instead :)
wc –(l or w or c) file counts total lines (l), words (w) and/or characters (c) in file
whereis command locates the binary, source, manual of command (see locate)

which command prints the location of command or the alias to which it points


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