Noun:
1. One who administers; one who manages, carries on, or directs the affairs of any establishment or institution.
2. One who has the faculty of managing or organizing.
3. One who executes or performs the official duties of religion, justice, etc.; one who dispenses or ministers to the public in such matters.
4. One to whom authority is given to manage estates, etc. for the legal owner during his minority, incapacity, etc.; a trustee, a steward. esp. in Sc. Law. `A person legally empowered to act for another whom the law presumes incapable of acting for himself' (Encyc.Brit.), as the father of children under age.
The following URL shows a “family tree” of the UNIX operating system: http://www.levenez.com/unix/history.html
Contents BSD System V Sections Sections User Commands 1 1 System Calls 2 2 C and other library routines 3 3 Special files, device drivers, hardware 4 7 Configuration files 5 4 Games 6 6 or 1 or NA Miscellaneous commands 7 5 Administration commands 8 1M Maintenance commands 8 8 Local commands l l
Common options (commonly used w/o dash): a print all processes involving terminals e print environment and arguments l long listing u print user information x include processes with no terminals Meaning of user information columns: %CPU percentage use of CPU SZ set size (in 1024 byte pages) of the process RSS resident set size (in pages) of the process STAT state of the process TIME time, including both user and system time
Common options (commonly used w/ dash): -e print all processes -f print full listing -l long listing (more info than -f) Meaning of full listing columns: S state PRI priority SZ set size (in 4096 byte pages) of the process STIME starting time TIME cumulative execution time
$ ps aux | grep sshd # is sshd running? $ ps fax | less # show process "tree" view
$ find starting-dir(s) matching-criteria-and-actions Matching criteria -atime n file was accessed n days ago -mtime n file was modified n days ago -size n file is exactly n 512-byte blocks -type c file type (e.g., f=plain, d=dir) -name nam file name (e.g., `*.c') -user usr file's owner is usr -perm p file's access mode is p Actions -print display pathname -exec cmd execute command ({} expands to file)
# Starting in current directory, find C source files $ find . -name '*.c' # Starting in root directory, find and list files that are # more than 30 days old and >30 MB in size $ find / -size +3M -mtime +30 -exec ls -l {} \;
aptitude less links mc mutt sudo vim vlock wget
$ dpkg -i foo-4.5.deb
# lists the packages installed on the system $ dpkg -l # remove the specified package from the system $ dpkg --remove package # completely remove the specified package $ dpkg --purge package # search for files within installed packages $ dpkg -S nslookup
$ apt-get install foo
apt-cache search search_string