UNIX 101

1
UNIX 101

• CS372 Operating Systems
• TA Roberto E. Lopez-Herrejon
• Spring 2002

2
ls

• List the contents of the file directories
• Syntax
• ls options files/patterns
• -l long format -a all the files
• -f sorts by name -r sorts reverse order
• -R lists dirs recursively
• Examples
• ls -l names2
• ls -f this.cpp

3
find

• Search for files in a file system
• Syntax
• find path expression
• path where the search is done
  for expression
• -name fname search for files that match
  fname expression
• -print send output to
  standard out
• -type file_type search for files of
  file_type
• f - file, d - directory, l -
  link
• Example
• find ./CS372/ -name "Example.cpp" print

4
cat

• Concatenate files and print on standard output
• Syntax
• cat options files
• -n numbers the output lines
• Examples
• cat -n file1 file2
• cat file1 file2 gt file3

5
tail

• Output the last part of a file
• Syntax
• tail - number lbcr file
• -l lines -b blocks
• -c bytes -r reverse
• Examples
• tail -10l README last 10 lines of file
  README
• tail 55l README last lines from 55th line

6
head

• Displays the first few lines of files
• Syntax
• head -n number filename
• head number filename
• Examples
• head -10 README
• head -n 10 README

7
mv

• Renames files
• Syntax
• mv options source dest
• mv options source... directory
• -v verbose -b makes backups
• -f force renaming -i prompts to overwrite
• Examples
• mv oldname newname
• mv -f files ./mydirect/

8
cp

• Copy files
• Syntax
• cp options source dest
• cp options source... directory
• -b makes backups -f forces copying
• -r copies files recursively -R copies
  directories recursively
• Examples
• cp -R directory1 directory2
• cp -f .cpp ./Project1/

9
rm

• Remove files
• Syntax
• rm -dfirvR path...
• -f forces removing -i interactive -v
  verbose
• -r or -R removes directories recursively
• Examples
• rm -i .cpp
• rm -R directory1

10
rmdir

• Remove empty directories
• Syntax
• rmdir -p dir...
• -p remove parent directories if directory
  becomes empty
• Examples
• rmdir directory1

11
mdkir

• Make directories
• Syntax
• mkdir -p dir...
• -p makes sure the path exists
• Examples
• mkdir directory1
• mkdir -p /full/path directory2

12
cmp

• Compare two files
• Syntax
• cmp -cls file1 file2
• -c prints differing characters -l vebose
  (line number)
• -s silence
• Output 0 - identical, 1 - differ, 2 - error
• Examples
• cmp -c myfile1 myfile2

13
diff

• Display line-by-line differences between files
• Syntax
• diff options filename1 filename2
• diff options directory1 directory2
• -a treat files as text
• -B ignore blank spaces differences
• -H uses heuristics for search
• Examples
• diff -a file1 file2
• diff -B file1 file2

14
chmod

• Change the access permissions of files
• Syntax
• chmod -Rcfv mode file...
• -R recursive changes -f silent
• -c verbose output of files changed -v verbose
  output
• mode symbolic representation (r,w,x,-,) or
  octal number for
• the new permissions
• Examples
• chmod 700 file1
• chmod x file2

15
ps

• Report process status
• Syntax
• ps options
• -a list all processes -l long listing of
  processes
• -e list running processes
• Examples
• ps -a
• PID PPID PGID WINPID TTY UID
  STIME COMMAND
• 652 1 652 652 con
  1003 102033 /usr/bin/bash

16
kill

• Send a signal to a process
• Syntax
• kill -signalnumber processid
• Examples
• kill -9 12312 sure kill
• kill -15 12342 default signal

17
turnin

• To submit your project, execute on a CS Unix
  machine
• /p/bin/turnin -submit rlopez cs372 ltfilegt
• To check your submissions
• /p/bin/turnin -list rlopez cs372

18
References

• Paul W. Abrahams, Bruce R. Larson
• Unix for the impatient, 2nd ed.
• Addison-Wesley, 1996
• http//www.cs.utexas.edu/users/UTCS/online-docs/
  cluesheets/