perl for unix and linux users

... In both Windows and Linux the serial port is treated as a file, and the file read and write operations are used to send 5 data to and from the port. These operations differ from standard file input/output ... specific appli- cation. 3.1.2 Linux Opening the serial port in Linux is performed in much the same way as it is in Windows, using the open() command. One caveat to Linux is that the user ID that ... is now opened and, in this case, fd is a handle to the opened device file. As can be seen, if the open() function call fails, the device handle is set to −1 and by checking the handle against

Ngày tải lên: 05/11/2013, 20:15

... Bauer Automating UNIX and Linux Administration CYAN MAGENTA YELLOW BLACK PANTONE 123 CV ISBN 1-59059-212-3 9 781590 592120 54999 6 89253 15123 5 www.apress.com Automating UNIX and Linux Administration ... ask for the key once ssh-add # Now, perform a bunch of SSH operations ssh host1 'command1' ssh host1 'command2' ssh host2 'command3' # Finally, kill the agent and ... systems to become more reliable and efficient every day. Kirk Bauer US $49.99 Shelve in Networking /UNIX/ Linux User level: Intermediate–Advanced forums.apress.com FOR PROFESSIONALS BY PROFESSIONALS

Ngày tải lên: 08/08/2014, 21:21

... on the system for each user who needs to run commands as root. 2.12.1 Preparing for Common Accounts The setup is actually very simple. You generate a key pair for each user and then list ... the system and nothing more. no-port-forwarding,command="/sbin/reboot",no-pty ssh-rsa AB YZ Whoever possesses the specified private key cannot open an interactive shell or forward ports. ... Chapter 2 of "Automating Unix and Linux Administration" (Apress, 2003; ISBN: 1-59059-212-3). Using SSH to Securely Automate System Administration 27 2.11.3 Port Forwarding There are plenty

Ngày tải lên: 08/08/2014, 21:21

... v, w, x and y are symbolic. Finally we see two function handles and two inline objects, corresponding to the pairs of anonymous functions and inline functions. The command whos shows information ... LEFT- and RIGHT- ARROW keys to move around in the command line, deleting and inserting changes as necessary, and then press E NTER to tell MATLAB to evaluate the modified command For ... workspace at the command prompt. Figure 2.2 depicts a Desktop in which the Command Window and the Workspace Browser contain the same informa- tion as displayed above. Variables and Assignments In

Ngày tải lên: 09/08/2014, 12:22

... overview of commands, type help graphics (for general graphics commands), help graph2d (for two-dimensional graphics commands), help graph3d (for three-dimensional graphics commands), and help ... converts other formats to and from wav The commands wavread and wavwrite read and write... color to white ✰ Images, Animations, and Sound MATLAB is also able to create and manipulate ... double-integral command dblquad, whose properties and use we will allow you to discover from the online help. Limits You can use limit to compute right- and left-handed limits and limits at infinity. For example,

Ngày tải lên: 09/08/2014, 12:22

... online help for varargout and the functions described above for additional information and examples Evaluation and Function Handles The command eval allows you to run a command that ... ✓ Like for and the other programming commands you will encounter, if and its associated commands can be used in the Command Window. Doing so can be useful for practice with these commands, but ... to it ✓ MATLAB also has signed and unsigned integer data types; see the online help for int32 and uint32, for example Commands for Parsing Input and Output You may have noticed that

Ngày tải lên: 09/08/2014, 12:22

... uitools for information on available dialog boxes Here is our callback function for the Push Button labeled “Clear figure”: set(handles.edit1, ’String’, ’’); set(handles.figure1, ’HandleVisibility’, ... can use the command sim from the command line or within an M-file. The simplest form of this command just runs the model with the existing parameters. But one can also use this command to set the ... solve for A in the equation that P = 0 after N payments solve (A* mˆN - R*(mˆN - 1)/(m - 1), A) ans = R*(mˆN-1)/(mˆN)/(m-1) For example, if one is shopping for a house and can afford

Ngày tải lên: 09/08/2014, 12:22

... and barley To produce these crops, it costs the farmer (for seed, fertilizer, etc.) $120 per acre for the wheat and $210 per acre for the barley The farmer has $15,000 available for ... without bound (for growing populations), and is therefore not realistic. Our next model allows for a check on the population caused by limited space, limited food supply, competitors, and predators. ... rand(n, k))) profits = @(n,k) sum(sign(0.51 - rand(n, k))) What this function does is to generate an n × k matrix of random numbers and then perform the same operations as above on each entry

Ngày tải lên: 09/08/2014, 12:22

... 0 to time 4, using boundary temperatures 15 and 25, and an initial temperature distribution of 15 for x<0 and 25 for x>0. We replace u(x, t) for fixed t by the vector u of values of u(x, ... x ≤ 5 from time 0 to time 4, using boundary temperatures 15 and 25, and an initial temperature distribution of 15 for x<0 and 25 for x>0. You can imagine that two separate wires of length ... can use for the derivatives, and this method can be refined by using more accurate approximations, especially for the t derivative.) Thus if, for a particular n, we know the values of u n j for all

Ngày tải lên: 09/08/2014, 12:22

... as input two expressions f and g (given either as symbolic expressions or as strings) and two numbers a and b, plots the functions f and g between x = a and x = b, and shades the region in between ... the M-file for common mistakes and syntax errors and prints out a report specifying where potential problems are located. (You can do the same thing from the Command Window with the command mlint ... the wrong type of input for the plotting command chosen. SOLUTION: Carefully follow the examples in the help lines of the plotting command, and pay attention to the error and warning messages.

Ngày tải lên: 09/08/2014, 12:22

... models and worse than others 3 (a) We can use the expression (rand < 0.338) to compute whether Tony gets a hit or not during a single at bat, based on a random number chosen between 0 and ... random numbers into this expression at once and sum the results, dividing by 500 to get his batting average for the year The following function does just this, allowing more generally for ... Below is a series of commands that places Picard at the center of the arena, fires the death ray 100 times, and. .. a hit; otherwise, the expression evaluates to 0 and Tony is retired by

Ngày tải lên: 09/08/2014, 12:22

... gratitude for all the good times we’ve had together brief contents Part Minimal Perl: for UNIX and Linux Users 1 Introducing Minimal Perl Perl essentials 16 Perl as a (better) grep command 53 Perl ... Minimal Perl: for UNIX and Linux Users 1 Introducing Minimal Perl 1.1 A visit to Perlistan 3 Sometimes you need a professional guide 1.2 Perl can be simple 1.3 About Minimal Perl What Minimal Perl ... grep command 53 Perl as a (better) sed command 89 Perl as a (better) awk command 121 Perl as a (better) find command 178 Part Minimal Perl: for UNIX and Linux Shell Programmers 203 Built-in functions...

Ngày tải lên: 25/03/2014, 10:27

... gratitude for all the good times we’ve had together brief contents Part Minimal Perl: for UNIX and Linux Users 1 Introducing Minimal Perl Perl essentials 16 Perl as a (better) grep command 53 Perl ... Minimal Perl: for UNIX and Linux Users 1 Introducing Minimal Perl 1.1 A visit to Perlistan 3 Sometimes you need a professional guide 1.2 Perl can be simple 1.3 About Minimal Perl What Minimal Perl ... grep command 53 Perl as a (better) sed command 89 Perl as a (better) awk command 121 Perl as a (better) find command 178 Part Minimal Perl: for UNIX and Linux Shell Programmers 203 Built-in functions...

Ngày tải lên: 06/08/2014, 03:20

... routinely in Minimal Perl and removed only in the rare cases where it spoils the results It’s shown here for both the sed and perl commands for uniformity PERL S INVOCATION OPTIONS 19 $ perl -wpl -e ... ' # Output Generation This next group is for commands that read input: alias alias alias alias perl_ io=' perl_ iop=' perl_ f=' perl_ fp=' perl perl perl perl -wnl -wpl -wnla -wpla ' ' ' ' # # # ... process input a paragraph at a time: alias alias alias alias alias Perl_ o=' Perl_ io=' Perl_ iop=' Perl_ f=' Perl_ fp=' perl perl perl perl perl -00 -00 -00 -00 -00 -wl -wnl -wpl -wnla -wpla ' ' ' ' '...

Ngày tải lên: 06/08/2014, 03:20

... Explanation /perl/ Looks for a match with perl in $_ Matches perl in $_ m :perl: Same, except uses different delimiters Matches perl in $_ $data =~ /perl/ i Looks for a match Matches perl PERL Perl ... Unix and Perl commands for common grepping activities Unix command Perl counterpart Type of task Section grep 'RE' F perl -wnl -e '/RE/ and print;' F Show matching lines 3.3.1 grep -v 'RE' F perl ... after consulting man ascii: 104 LHS and RHS, respectively, stand for left- and right-hand-side, and DQ stands for double quotes CHAPTER PERL AS A (BETTER) sed COMMAND ...

Ngày tải lên: 06/08/2014, 03:20

... of AWK and Perl next NOTE 5.2 AWK is totally AWKsome, but Perl is even better; it’s Perlicious! COMPARING BASIC FEATURES OF awk AND PERL This section provides an overview of how AWK and Perl compare ... $total, as in $total += $_ CHAPTER PERL AS A (BETTER) awk COMMAND Table 5.8 AWK and Perl programs for simple tasks AWK a Perl b Explanation

Ngày tải lên: 06/08/2014, 03:20

... '-A and ! -B and print;' # Example perl -wnl -e '-A and -B and -C and print;' # Example perl -wnl -e '( -A or -B ) and print;' # Example perl -wnl -e '( -A or -B or -C ) and print;' # Example perl ... Then Perl commands, having forms such as these, could be added as the filtering stage in the pipeline: perl -wnl -e '-A and print;' # Example perl -wnl -e '-A and -B and print;' # Example perl ... use a special kind of find | perl pipeline for filtering out undesirable arguments for Unix utilities, and how to use Unix utilities for validating arguments for Perl programs 6.4 PROCESSING...

Ngày tải lên: 06/08/2014, 03:20

... Table 7.7 The rand function Typical invocation formats $random_tiny_number=rand; $random_larger_number=rand N; $random_element=$some_array[ rand @some_array ]; Example Explanation $num=rand; Assigns ... nearest relative in Unix or the Shell Table 7.8 Useful Perl functions for lists, and their nearest relatives in Unix Built-in Perl function Unix relative(s) sort The Unix sort command List sorting ... similarities and differences in how data flows between commands and functions 7.3.1 Comparing Unix pipelines and Perl functions Although there are distinct similarities between Unix command pipelines and...

Ngày tải lên: 06/08/2014, 03:20

... back-quote syntax for command substitution, of the form $(command) INTERPOLATING COMMAND OUTPUT INTO SOURCE CODE 269 Table 8.6 Command substitution/interpolation in the Shell and Perl Shell a Perl Explanation ... separated records a cmd and cmd2 represent OS commands, var/$var and array/@array Shell /Perl variable names, and function a Perl function name When a Unix shell processes a command substitution, a ... submit a command to the OS-dependent command interpreter (/bin/sh on Unix) for execution 18 See http://TeachMePerl.com/DQs_in_shell_vs _perl. html for further details EXECUTING OS COMMANDS USING...

Ngày tải lên: 06/08/2014, 03:20

... quality value The Shell’s for loop is similar to Perl s foreach loop, not Perl s for loop LOOPING WITH for Although the Shell’s for is like Perl s foreach, Perl does have a for loop of its own, derived ... variable The syntax for the Shell’s for loop is shown in table 10.5 alongside that of its Perl counterpart, foreach Table 10.5 The Shell’s for loop and Perl s foreach loop Shell a Perl for var in LIST ... $index=rand @fortunes; # select random index CHAPTER LIST VARIABLES 27 28 29 30 31 32 printf $fortunes[ $index ]; # print random fortune delete $fortunes[ $index ]; # mark fortune undefined @fortunes=grep...

Ngày tải lên: 06/08/2014, 03:20