System Software

Diomidis Spinellis
Department of Management Science and Technology
Athens University of Economics and Business
Athens, Greece
dds@aueb.gr

Operating System

Linux
OpenSolaris
FreeBSD
OpenBSD

Command Line Tools

1000-5000 commands in a typical operating system installation.

Archivers
Audio
Databases
Development
Documentation
Graphics
Interpreters
Math
Network and web
Security

The package manager is your friend!

Scripting Language

Groovy
Perl
Python
Ruby

The Unix Toolchest

Available under Unix, GNU/Linux, *BSD.

For Windows:

Cygwin (http://www.cygwin.com/)
MinGW (http://www.mingw.org/)
UnxUtils (http://unxutils.sourceforge.net/)
UWin (http://www.research.att.com/sw/tools/uwin/)
Outwit (http://www.spinellis.gr/sw/outwit) (Windows integration)

Working with Unix Tools

Fetch or generate data
Selection
Processing
Summarizing
Program development

Data Fetching and Generation

nm: object files
nm, ldd: executables
tar: archives
ar, jar: libraries
find: directory hierarchies
wget: the web
cvs or svn log or annotate: version control
jot or dd: generate artificial data

Selection

awk: delimited records
cut: fixed width files
sed: select row parts with regular expressions
grep: select rows with regular expressions
Combine the above in pipelines

Processing

sort: order by multiple keys
uniq: remove duplicates, count
diff: compare sequential files
comm: compare ordered lists
tr: map between character sets
recode: map between text representations
tac/rev: reverse order of lines, characters
rs: reshape arrays
join: relational join
Scripting languages handle more complex tasks

Summarizing

wc: count lines, characters
head: first elements
tail: last elements
fmt: format into lines
awk with an END block

Plumbing

Pass data through pipeline
tee: tap output for further processing
xargs: apply command to numerous arguments
Pipe into a while loop for complicated processing

Example: Analyze Java Files

Examine all Java files located in the directory src, and print the ten files with the highest number of occurrences of a method call to substring.

find src -name ’*.java’ -print |
xargs fgrep -c .substring |
sort -t: -rn -k2 |
head -10

Example: Determine Commit Times

find . -type f |
grep -v CVS |
xargs cvs -d /home/ncvs log -SN 2>/dev/null |
awk '/^date/{
    hour = substr($3, 0, 2)
    lines[$5 " " hour] += $9
  }
END {
    for (i in lines) print i, lines[i]
  }' |
sed 's/;//g' |
sort >dev-times-lines.dat
join dev-times-lines.dat devlong >dev-times-lines-long.dat

Example Result:Plotted Commit Times

Program Development

Editors
GNU Compiler Collection
Language development tools (bison, flex)
Tracers and debuggers
Profilers
Code formatting tools (cb, indent)
Version control systems

(More on the above later.)

Outwit Tools

winclip - Access the windows clipboard
winreg - manipulate the windows registry
docprop - read document properties
odbc - select data from relational databases
readlink - resolve shell shortcuts
readlog - access the windows event log

Outwit Examples

Create an list of fax recipients ordered by the number of faxes they have received.

readlog Application |
awk -F: "/Outbound: Information: Fax Sent/{print $12}" |
sort |
uniq -c |
sort -rn

Extracts the email address from all records from the table users which is part of the database userDB and sends them the file message by email.

fmt message |
mail $(odbc DSN=userDB "select email from users")

An Editor Checklist

Regular expressions
Syntax coloring
Folding
Error highlighting
Indentation
Marking of matching delimiters
On-line help for API elements
Code browsing
Multiple buffers
Macros
Refactoring support

Two candidates: Emacs, vim.

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