WEB HOSTING Y DISEñO DE PÁGINAS WEB

man – Online UNIX manual (“ man- pages”).
Gives detailed instructions on all of the commands listedhere and a lot more.
cat filename1 > filename2 – Overwrite contents of
filename2 with filename1 .
cat filename1 » filename2 – Append contents of
filename1 to filename2 .
cd /usr – Change current directory to /usr .
cd .. – Change current directory to previous higher
directory.
cd – Change to home of current userid.
chgrp group1 filename1 – Change group id to group 1 for filename1 .
chgrp - R group1 * – Change group id of all files in
current and subdirectories to group 1 .
chmod ugo+ rwx filename1 – Add read/ write/ execute
permission to filename1 for user/ owner, group and others (world).
chmod ox filename1 – Remove execute from others (world).
chmod 751 filename1 – Set rwx for user/ owner, rx for group and x for others. 
rwx= 421, r= 4, w= 2, x= 1 rx= 5x= 7x= 1.
chown sam filename1 – Change owner of file
filename1 to sam .
chown -R sam * – Change owner to sam for all files incurrent and subdirectories.
clear – Clear the terminal screen.
compress filename1 – Compress file filename1 . See also uncompress .
cp filename1 filename2 – Copy file filename1 to
filename2 destroying the contents of filename2.
cp -i * /usr/ local/ bin – Copy all files in current
directory to /usr/ local/ bin directory. Prompt before overwriting files ( i ).
cpio – Copy file archives to disk/ tape. See man pages.
crontab -e – Edit crontab file for userid.
crontab -e bill – Edit crontab file for user bill .
crontab -l – List crontab entries for current userid.
csh – Start the c shell process. See man pages.
cut d: f1, 5 /etc/ passwd – Extract username & real names from file /etc/ passwd  where
delimiter is colon getting fields 1 & 5.
who | cut d" " f1 – List login names from who
command.
date – Display current date string.
date +% D – Display current date as 11/ 21/ 94 format.
dd – Copy file( s) to/ from raw devices. See man pages.
df – Display free disk blocks and modes on file systems.
df -k – Display free space in kilobytes for mounted file systems.
echo name – Displays literal "name" on screen.
echo $PATH – Displays PATH environment variable.
ed/ edit/ ex – Alternative line editors, see vi .
env – Displays current environment variables or allows setting.
file filename1 – Determines and displays type of file
for filename1 (text, data, executable, directory,
symbolic link... etc...).
find /usr/ opt/ bin -name "filename1*" -print – Starts
searching in /usr/ opt/
bin for files starting with
filename1 . If found prints the full file names and
continues searching subdirectories.
find . -type f -print | xargs grep -i [PATTERN] –
Recursive grep for a pattern in a file (searches through files in subdirectories).
find . ! -mtime -< days> | /usr/ bin/ xargs rm -rf –
Finds and removes files older than <days> specified.
finger sam – Displays data about user session for sam .
ftp solar – Establishes a File Transfer Protocol session
over the network between current host and a host
named sola r. See man pages for additional ftp
commands.
grep jdoe /etc/ passwd – Searches the file /etc/ passwd searching for string "jdoe" . If found, displays
grep -i Sam filename1 – Search filename1 for upper or lower case string of  Sam and display lines found.