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  • How can I mix command line arguments and filenames for <> in Perl?

    - by Jimmeh
    Consider the following silly Perl program: $firstarg = $ARGV[0]; print $firstarg; $input = <>; print $input; I run it from a terminal like: perl myprog.pl sample_argument And get this error: Can't open sample_argument: No such file or directory at myprog.pl line 5. Any ideas why this is? When it gets to the < is it trying to read from the (non-existent) file, "sample_argument" or something? And why?

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  • How can I initialize a 2d array in Perl?

    - by Mark
    How do I initialize a 2d array in perl? I am trying the following code: 0 use strict; 10 my @frame_events = (((1) x 10), ((1) x 10)); 20 print "$frame_events[1][1]\n"; but it gives the following error: Can't use string ("1") as an ARRAY ref while "strict refs" in use at ./dyn_pf.pl line 20. This syntax only seems to initialize a 1d array as print "$frame_events[1]\n" works. Though perl doesn't give any error during the assignment.

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  • How can I use Awk inside a Perl script?

    - by papoyan
    I'm having trouble using the following code inside my Perl script, any advise is really appreciated, how to correct the syntax? # If I execute in bash, it's working just fine bash$ whois google.com | egrep "\w+([._-]\w)*@\w+([._-]\w)*\.\w{2,4}" |awk ' {for (i=1;i<=NF;i++) {if ( $i ~ /[[:alpha:]]@[[:alpha:]]/ ) { print $i}}}'|head -n1 [email protected] #----------------------------------- #but this doesn't work bash$ ./email.pl google.com awk: {for (i=1;i<=NF;i++) {if ( ~ /[[:alpha:]]@[[:alpha:]]/ ) { print }}} awk: ^ syntax error # Here is my script bash$ cat email.pl ####\#!/usr/bin/perl $input = lc shift @ARGV; $host = $input; my $email = `whois $host | egrep "\w+([._-]\w)*@\w+([._-]\w)*\.\w{2,4}" |awk ' {for (i=1;i<=NF;i++) {if ( $i ~ /[[:alpha:]]@[[:alpha:]]/ ) { print $i}}}'|head -1`; print my $email; bash$

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  • What does it mean when a Perl method returns a "hashref"?

    - by Uri
    I'm trying to decrypt a Perl code which I'm not familiar with, somehow related to HashRef. I'm using Amazon::S3, but my question is a general Perl question. See the code below: use Amazon::S3; my $s3 = Amazon::S3->new( ... ); my $response = $s3->buckets; Documentation (here) sais, about s3-buckets: Returns undef on error, else HASHREF of results The following line is working for me, but I don't understand why: for $b in ( @ { $response->{buckets} } ) { print "bucket: " . $b->bucket . "\n"; } I'm Puzzled by each operator on the first line. What type exactly are $response, $respone->{bucket}. Looks like the expression within the for is an array, but I don't understand this syntax: @{ ... }?

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  • how to escape slashes in perl command in unix script?

    - by understack
    end_date=$(date +"%m/%d/%Y") /usr/bin/perl -pi -e "s/_end_date_/${end_date}/g" filename I want to replace string '_end_date_' with current date. Since current date has slashes in it(yes I want the slashes), I need to escape them. How can I do this? I've tried several ways like replacing slashes with "\/" using sed and perl itself but it didn't work. Finally I used 'cut' to break date in 3 parts and escaped slashes but this solution doesn't look good. Any better solution?

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  • How do I get the output from a Perl pipe as it becomes available?

    - by Uri
    The following code is working sort of fine: open( PIPE, '-|', 'ant' ); for( <PIPE> ) { print; } However, it doesn't do what I want. Since the Ant build can take 5 minutes, I would like to see the output line by line. Instead, I'm getting the entire input at the end of the process. Looking at it with the Perl debugger, Perl waits at the 'for' statement, until Ant terminates. Why is that?

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  • kernel module compiling error

    - by wati
    sh@ubuntu:/home/ccpp/helloworld$ make gcc-4.6 -O2 -DMODULE -D_KERNEL_ -W -Wall -Wstrict-prototypes -Wmissing-prototypes -isystem /lib/modules/`uname -r`/build/include -c -o hello-1.o hello-1.c hello-1.c:4:0: warning: "MODULE" redefined [enabled by default] <command-line>:0:0: note: this is the location of the previous definition hello-1.c:6:0: warning: "_KERNEL_" redefined [enabled by default] <command-line>:0:0: note: this is the location of the previous definition In file included from /lib/modules/3.2.0-25-generic/build/include/linux/list.h:4:0, from /lib/modules/3.2.0-25-generic/build/include/linux/module.h:9, from hello-1.c:7: /lib/modules/3.2.0-25-generic/build/include/linux/types.h:13:2: warning: #warning "Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders" [-Wcpp] In file included from /lib/modules/3.2.0-25-generic/build/include/linux/module.h:9:0, from hello-1.c:7: /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘INIT_LIST_HEAD’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:26:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:27:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__list_add’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:41:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:42:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:43:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:44:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_add’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:62:28: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_add_tail’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:76:22: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__list_del’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:88:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:89:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__list_del_entry’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:101:18: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:101:31: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_del’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:106:18: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:106:31: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:107:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:108:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_replace’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:125:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:125:17: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:126:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:127:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:127:17: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:128:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_is_last’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:179:13: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_empty’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:188:13: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_empty_careful’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:206:31: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:207:40: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_rotate_left’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:219:15: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_is_singular’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:230:35: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:230:49: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__list_cut_position’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:236:37: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:237:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:237:19: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:238:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:239:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:240:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:241:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:242:11: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_cut_position’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:265:8: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__list_splice’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:277:32: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:278:31: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:280:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:281:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:283:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:284:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_splice’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:296:33: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_splice_tail’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:308:27: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_splice_init’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:322:33: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘list_splice_tail_init’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:339:27: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘INIT_HLIST_NODE’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:572:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:573:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_unhashed’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:578:11: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_empty’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:583:11: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘__hlist_del’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:588:29: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:589:31: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:592:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_del’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:598:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:599:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_add_head’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:612:30: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:613:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:615:8: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:615:20: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:616:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:617:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:617:15: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_add_before’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:624:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:624:17: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:625:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:626:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:626:18: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:627:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_add_after’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:633:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:633:16: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:634:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:635:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:635:18: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:637:9: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:638:7: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:638:29: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_add_fake’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:644:3: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:644:15: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h: In function ‘hlist_move_list’: /lib/modules/3.2.0-25-generic/build/include/linux/list.h:654:5: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:654:18: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:655:9: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:656:6: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:656:27: error: dereferencing pointer to incomplete type /lib/modules/3.2.0-25-generic/build/include/linux/list.h:657:5: error: dereferencing pointer to incomplete type In file included from /lib/modules/3.2.0-25-generic/build/include/linux/module.h:12:0, from hello-1.c:7: /lib/modules/3.2.0-25-generic/build/include/linux/cache.h: At top level: /lib/modules/3.2.0-25-generic/build/include/linux/cache.h:5:23: fatal error: asm/cache.h: No such file or directory compilation terminated. make: *** [hello-1.o] Error 1 i got this error after compiling an helloworld program my program is #define MODULE #define LINUX #define _KERNEL_ #include <linux/module.h> #include <linux/kernel.h> int init_module(void) { printk("<1>hello World 1.\n"); return 0; } void cleanup_module(void) { printk(KERN_ALERT "goodbye world 1.\n"); } MODULE_LICENSE("GPL"); my make file is: TARGET := hello-1 WARN := -W -Wall -Wstrict-prototypes -Wmissing-prototypes INCLUDE := -isystem /lib/modules/`uname -r`/build/include CFLAGS := -O2 -DMODULE -D_KERNEL_ ${WARN} ${INCLUDE} CC := gcc-4.6 ${TARGET}.o: ${TARGET}.c .PHONY: clean clean: rm -rf ${TARGET}.o iam usin kernel 3.2.0.25 as novice i can't able to figure out where the problem is I SEARCHED EVERY THING I CAN TO KNOW ABOUT THIS ERROR BUT I CANT UNDERSTAND &I GET IRRELEVANT DOCS anybody help me please

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  • Organizations &amp; Architecture UNISA Studies &ndash; Chap 7

    - by MarkPearl
    Learning Outcomes Name different device categories Discuss the functions and structure of I/.O modules Describe the principles of Programmed I/O Describe the principles of Interrupt-driven I/O Describe the principles of DMA Discuss the evolution characteristic of I/O channels Describe different types of I/O interface Explain the principles of point-to-point and multipoint configurations Discuss the way in which a FireWire serial bus functions Discuss the principles of InfiniBand architecture External Devices An external device attaches to the computer by a link to an I/O module. The link is used to exchange control, status, and data between the I/O module and the external device. External devices can be classified into 3 categories… Human readable – e.g. video display Machine readable – e.g. magnetic disk Communications – e.g. wifi card I/O Modules An I/O module has two major functions… Interface to the processor and memory via the system bus or central switch Interface to one or more peripheral devices by tailored data links Module Functions The major functions or requirements for an I/O module fall into the following categories… Control and timing Processor communication Device communication Data buffering Error detection I/O function includes a control and timing requirement, to coordinate the flow of traffic between internal resources and external devices. Processor communication involves the following… Command decoding Data Status reporting Address recognition The I/O device must be able to perform device communication. This communication involves commands, status information, and data. An essential task of an I/O module is data buffering due to the relative slow speeds of most external devices. An I/O module is often responsible for error detection and for subsequently reporting errors to the processor. I/O Module Structure An I/O module functions to allow the processor to view a wide range of devices in a simple minded way. The I/O module may hide the details of timing, formats, and the electro mechanics of an external device so that the processor can function in terms of simple reads and write commands. An I/O channel/processor is an I/O module that takes on most of the detailed processing burden, presenting a high-level interface to the processor. There are 3 techniques are possible for I/O operations Programmed I/O Interrupt[t I/O DMA Access Programmed I/O When a processor is executing a program and encounters an instruction relating to I/O it executes that instruction by issuing a command to the appropriate I/O module. With programmed I/O, the I/O module will perform the requested action and then set the appropriate bits in the I/O status register. The I/O module takes no further actions to alert the processor. I/O Commands To execute an I/O related instruction, the processor issues an address, specifying the particular I/O module and external device, and an I/O command. There are four types of I/O commands that an I/O module may receive when it is addressed by a processor… Control – used to activate a peripheral and tell it what to do Test – Used to test various status conditions associated with an I/O module and its peripherals Read – Causes the I/O module to obtain an item of data from the peripheral and place it in an internal buffer Write – Causes the I/O module to take an item of data form the data bus and subsequently transmit that data item to the peripheral The main disadvantage of this technique is it is a time consuming process that keeps the processor busy needlessly I/O Instructions With programmed I/O there is a close correspondence between the I/O related instructions that the processor fetches from memory and the I/O commands that the processor issues to an I/O module to execute the instructions. Typically there will be many I/O devices connected through I/O modules to the system – each device is given a unique identifier or address – when the processor issues an I/O command, the command contains the address of the address of the desired device, thus each I/O module must interpret the address lines to determine if the command is for itself. When the processor, main memory and I/O share a common bus, two modes of addressing are possible… Memory mapped I/O Isolated I/O (for a detailed explanation read page 245 of book) The advantage of memory mapped I/O over isolated I/O is that it has a large repertoire of instructions that can be used, allowing more efficient programming. The disadvantage of memory mapped I/O over isolated I/O is that valuable memory address space is sued up. Interrupts driven I/O Interrupt driven I/O works as follows… The processor issues an I/O command to a module and then goes on to do some other useful work The I/O module will then interrupts the processor to request service when is is ready to exchange data with the processor The processor then executes the data transfer and then resumes its former processing Interrupt Processing The occurrence of an interrupt triggers a number of events, both in the processor hardware and in software. When an I/O device completes an I/O operations the following sequence of hardware events occurs… The device issues an interrupt signal to the processor The processor finishes execution of the current instruction before responding to the interrupt The processor tests for an interrupt – determines that there is one – and sends an acknowledgement signal to the device that issues the interrupt. The acknowledgement allows the device to remove its interrupt signal The processor now needs to prepare to transfer control to the interrupt routine. To begin, it needs to save information needed to resume the current program at the point of interrupt. The minimum information required is the status of the processor and the location of the next instruction to be executed. The processor now loads the program counter with the entry location of the interrupt-handling program that will respond to this interrupt. It also saves the values of the process registers because the Interrupt operation may modify these The interrupt handler processes the interrupt – this includes examination of status information relating to the I/O operation or other event that caused an interrupt When interrupt processing is complete, the saved register values are retrieved from the stack and restored to the registers Finally, the PSW and program counter values from the stack are restored. Design Issues Two design issues arise in implementing interrupt I/O Because there will be multiple I/O modules, how does the processor determine which device issued the interrupt? If multiple interrupts have occurred, how does the processor decide which one to process? Addressing device recognition, 4 general categories of techniques are in common use… Multiple interrupt lines Software poll Daisy chain Bus arbitration For a detailed explanation of these approaches read page 250 of the textbook. Interrupt driven I/O while more efficient than simple programmed I/O still requires the active intervention of the processor to transfer data between memory and an I/O module, and any data transfer must traverse a path through the processor. Thus is suffers from two inherent drawbacks… The I/O transfer rate is limited by the speed with which the processor can test and service a device The processor is tied up in managing an I/O transfer; a number of instructions must be executed for each I/O transfer Direct Memory Access When large volumes of data are to be moved, an efficient technique is direct memory access (DMA) DMA Function DMA involves an additional module on the system bus. The DMA module is capable of mimicking the processor and taking over control of the system from the processor. It needs to do this to transfer data to and from memory over the system bus. DMA must the bus only when the processor does not need it, or it must force the processor to suspend operation temporarily (most common – referred to as cycle stealing). When the processor wishes to read or write a block of data, it issues a command to the DMA module by sending to the DMA module the following information… Whether a read or write is requested using the read or write control line between the processor and the DMA module The address of the I/O device involved, communicated on the data lines The starting location in memory to read from or write to, communicated on the data lines and stored by the DMA module in its address register The number of words to be read or written, communicated via the data lines and stored in the data count register The processor then continues with other work, it delegates the I/O operation to the DMA module which transfers the entire block of data, one word at a time, directly to or from memory without going through the processor. When the transfer is complete, the DMA module sends an interrupt signal to the processor, this the processor is involved only at the beginning and end of the transfer. I/O Channels and Processors Characteristics of I/O Channels As one proceeds along the evolutionary path, more and more of the I/O function is performed without CPU involvement. The I/O channel represents an extension of the DMA concept. An I/O channel ahs the ability to execute I/O instructions, which gives it complete control over I/O operations. In a computer system with such devices, the CPU does not execute I/O instructions – such instructions are stored in main memory to be executed by a special purpose processor in the I/O channel itself. Two types of I/O channels are common A selector channel controls multiple high-speed devices. A multiplexor channel can handle I/O with multiple characters as fast as possible to multiple devices. The external interface: FireWire and InfiniBand Types of Interfaces One major characteristic of the interface is whether it is serial or parallel parallel interface – there are multiple lines connecting the I/O module and the peripheral, and multiple bits are transferred simultaneously serial interface – there is only one line used to transmit data, and bits must be transmitted one at a time With new generation serial interfaces, parallel interfaces are becoming less common. In either case, the I/O module must engage in a dialogue with the peripheral. In general terms the dialog may look as follows… The I/O module sends a control signal requesting permission to send data The peripheral acknowledges the request The I/O module transfers data The peripheral acknowledges receipt of data For a detailed explanation of FireWire and InfiniBand technology read page 264 – 270 of the textbook

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  • Ubuntu 12.04 OpenCL with Intel and Radeon?

    - by Steve
    I want to setup my Ubuntu 12.04 with OpenCL(Open Computing Language) support for i7 2600k and Radeon HD5870. My Monitor is connected to the integrated Graphics of the i7. Intel OpenCL SDK is installed and working. Iteration of avaliable OpenCL devices shows 2 entries for Intel. As recommended I installed AMD APP SDK 2.6 first and then the fglrx driver. I installed fglrx from Ubuntu repositories. This works fine till here. When I run aticonfig --inital -f and restart the system I get into trouble. Xorg starts only in low-graphics mode. cat /var/log/Xorg.0.log [ 21.201] X.Org X Server 1.12.2 Release Date: 2012-05-29 [ 21.201] X Protocol Version 11, Revision 0 [ 21.201] Build Operating System: Linux 2.6.24-29-xen x86_64 Ubuntu [ 21.201] Current Operating System: Linux chimera 3.2.0-24-generic #39-Ubuntu SMP Mon May 21 16:52:17 UTC 2012 x86_ [ 21.201] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-3.2.0-24-generic root=UUID=c137757b-486b-4514-9dfe-00c97662 [ 21.201] Build Date: 05 June 2012 08:35:55AM [ 21.201] xorg-server 2:1.12.2+git20120605+server-1.12-branch.aaf48906-0ubuntu0ricotz~precise (For technical suppor [ 21.201] Current version of pixman: 0.26.0 [ 21.201] Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. [ 21.201] Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. [ 21.201] (==) Log file: "/var/log/Xorg.0.log", Time: Fri Jun 8 14:22:36 2012 [ 21.247] (==) Using config file: "/etc/X11/xorg.conf" [ 21.247] (==) Using system config directory "/usr/share/X11/xorg.conf.d" [ 21.450] (==) ServerLayout "aticonfig Layout" [ 21.450] (**) |-->Screen "aticonfig-Screen[0]-0" (0) [ 21.450] (**) | |-->Monitor "aticonfig-Monitor[0]-0" [ 21.451] (**) | |-->Device "aticonfig-Device[0]-0" [ 21.451] (==) Automatically adding devices [ 21.451] (==) Automatically enabling devices [ 21.466] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist. [ 21.466] Entry deleted from font path. [ 21.466] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist. [ 21.466] Entry deleted from font path. [ 21.466] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist. [ 21.466] Entry deleted from font path. [ 21.473] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist. [ 21.473] Entry deleted from font path. [ 21.473] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist. [ 21.473] Entry deleted from font path. [ 21.473] (WW) The directory "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType" does not exist. [ 21.473] Entry deleted from font path. [ 21.473] (==) FontPath set to: /usr/share/fonts/X11/misc, /usr/share/fonts/X11/Type1, built-ins [ 21.473] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib [ 21.473] (II) The server relies on udev to provide the list of input devices. If no devices become available, reconfigure udev or disable AutoAddDevices. [ 21.473] (II) Loader magic: 0x7f0ad3b9ab00 [ 21.473] (II) Module ABI versions: [ 21.473] X.Org ANSI C Emulation: 0.4 [ 21.473] X.Org Video Driver: 12.0 [ 21.473] X.Org XInput driver : 16.0 [ 21.473] X.Org Server Extension : 6.0 [ 21.473] (--) PCI:*(0:0:2:0) 8086:0122:1458:d000 rev 9, Mem @ 0xfb800000/4194304, 0xe0000000/268435456, I/O @ 0x00 [ 21.473] (--) PCI: (0:1:0:0) 1002:6898:1787:2289 rev 0, Mem @ 0xd0000000/268435456, 0xfbdc0000/131072, I/O @ 0x000 [ 21.473] (II) Open ACPI successful (/var/run/acpid.socket) [ 21.473] (II) "extmod" will be loaded by default. [ 21.473] (II) "dbe" will be loaded by default. [ 21.473] (II) "glx" will be loaded. This was enabled by default and also specified in the config file. [ 21.473] (II) "record" will be loaded by default. [ 21.473] (II) "dri" will be loaded by default. [ 21.473] (II) "dri2" will be loaded by default. [ 21.473] (II) LoadModule: "glx" [ 21.732] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/extra-modules.dpkg-tmp/modules/extensions/libgl [ 21.934] (II) Module glx: vendor="Advanced Micro Devices, Inc." [ 21.934] compiled for 6.9.0, module version = 1.0.0 [ 21.934] (II) Loading extension GLX [ 21.934] (II) LoadModule: "extmod" [ 22.028] (II) Loading /usr/lib/xorg/modules/extensions/libextmod.so [ 22.041] (II) Module extmod: vendor="X.Org Foundation" [ 22.041] compiled for 1.12.2, module version = 1.0.0 [ 22.041] Module class: X.Org Server Extension [ 22.041] ABI class: X.Org Server Extension, version 6.0 [ 22.041] (II) Loading extension MIT-SCREEN-SAVER [ 22.041] (II) Loading extension XFree86-VidModeExtension [ 22.041] (II) Loading extension XFree86-DGA [ 22.041] (II) Loading extension DPMS [ 22.041] (II) Loading extension XVideo [ 22.041] (II) Loading extension XVideo-MotionCompensation [ 22.041] (II) Loading extension X-Resource [ 22.041] (II) LoadModule: "dbe" [ 22.041] (II) Loading /usr/lib/xorg/modules/extensions/libdbe.so [ 22.066] (II) Module dbe: vendor="X.Org Foundation" [ 22.066] compiled for 1.12.2, module version = 1.0.0 [ 22.066] Module class: X.Org Server Extension [ 22.066] ABI class: X.Org Server Extension, version 6.0 [ 22.066] (II) Loading extension DOUBLE-BUFFER [ 22.066] (II) LoadModule: "record" [ 22.066] (II) Loading /usr/lib/xorg/modules/extensions/librecord.so [ 22.077] (II) Module record: vendor="X.Org Foundation" [ 22.077] compiled for 1.12.2, module version = 1.13.0 [ 22.077] Module class: X.Org Server Extension [ 22.077] ABI class: X.Org Server Extension, version 6.0 [ 22.077] (II) Loading extension RECORD [ 22.077] (II) LoadModule: "dri" [ 22.077] (II) Loading /usr/lib/xorg/modules/extensions/libdri.so [ 22.082] (II) Module dri: vendor="X.Org Foundation" [ 22.082] compiled for 1.12.2, module version = 1.0.0 [ 22.082] ABI class: X.Org Server Extension, version 6.0 [ 22.082] (II) Loading extension XFree86-DRI [ 22.082] (II) LoadModule: "dri2" [ 22.082] (II) Loading /usr/lib/xorg/modules/extensions/libdri2.so [ 22.083] (II) Module dri2: vendor="X.Org Foundation" [ 22.083] compiled for 1.12.2, module version = 1.2.0 [ 22.083] ABI class: X.Org Server Extension, version 6.0 [ 22.083] (II) Loading extension DRI2 [ 22.083] (II) LoadModule: "fglrx" [ 22.083] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/extra-modules.dpkg-tmp/modules/drivers/fglrx_dr [ 22.399] (II) Module fglrx: vendor="FireGL - ATI Technologies Inc." [ 22.399] compiled for 1.4.99.906, module version = 8.96.4 [ 22.399] Module class: X.Org Video Driver [ 22.399] (II) Loading sub module "fglrxdrm" [ 22.399] (II) LoadModule: "fglrxdrm" [ 22.399] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/extra-modules.dpkg-tmp/modules/linux/libfglrxdr [ 22.445] (II) Module fglrxdrm: vendor="FireGL - ATI Technologies Inc." [ 22.445] compiled for 1.4.99.906, module version = 8.96.4 [ 22.445] (II) ATI Proprietary Linux Driver Version Identifier:8.96.4 [ 22.445] (II) ATI Proprietary Linux Driver Release Identifier: 8.96.7 [ 22.445] (II) ATI Proprietary Linux Driver Build Date: Mar 12 2012 13:06:50 [ 22.445] (++) using VT number 7 [ 22.445] (WW) Falling back to old probe method for fglrx [ 23.043] (II) Loading PCS database from /etc/ati/amdpcsdb [ 23.082] (--) Chipset Supported AMD Graphics Processor (0x6898) found [ 23.107] (WW) fglrx: No matching Device section for instance (BusID PCI:0@1:0:1) found [ 23.107] (II) fglrx: intel VGA device detected, load intel driver. [ 23.107] (II) LoadModule: "intel" [ 23.211] (II) Loading /usr/lib/xorg/modules/drivers/intel_drv.so [ 23.475] (II) Module intel: vendor="X.Org Foundation" [ 23.475] compiled for 1.12.2, module version = 2.19.0 [ 23.475] Module class: X.Org Video Driver [ 23.475] ABI class: X.Org Video Driver, version 12.0 [ 23.476] ukiDynamicMajor: found major device number 249 [ 23.476] ukiDynamicMajor: found major device number 249 [ 23.476] ukiOpenByBusid: Searching for BusID PCI:1:0:0 [ 23.476] ukiOpenDevice: node name is /dev/ati/card0 [ 23.476] ukiOpenDevice: open result is 8, (OK) [ 23.476] ukiOpenByBusid: ukiOpenMinor returns 8 [ 23.476] ukiOpenByBusid: ukiGetBusid reports PCI:1:0:0 [ 23.540] (WW) PowerXpress feature is not supported [ 23.540] (EE) No devices detected. [ 23.540] (==) Matched intel as autoconfigured driver 0 [ 23.540] (==) Matched vesa as autoconfigured driver 1 [ 23.540] (==) Matched fbdev as autoconfigured driver 2 [ 23.540] (==) Assigned the driver to the xf86ConfigLayout [ 23.540] (II) LoadModule: "intel" [ 23.540] (II) Loading /usr/lib/xorg/modules/drivers/intel_drv.so [ 23.540] (II) Module intel: vendor="X.Org Foundation" [ 23.540] compiled for 1.12.2, module version = 2.19.0 [ 23.540] Module class: X.Org Video Driver [ 23.540] ABI class: X.Org Video Driver, version 12.0 [ 23.540] (II) UnloadModule: "intel" [ 23.540] (II) Unloading intel [ 23.540] (II) Failed to load module "intel" (already loaded, 32522) [ 23.540] (II) LoadModule: "vesa" [ 23.583] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so [ 23.620] (II) Module vesa: vendor="X.Org Foundation" [ 23.620] compiled for 1.12.2, module version = 2.3.1 [ 23.620] Module class: X.Org Video Driver [ 23.620] ABI class: X.Org Video Driver, version 12.0 [ 23.620] (II) LoadModule: "fbdev" [ 23.620] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so [ 23.661] (II) Module fbdev: vendor="X.Org Foundation" [ 23.661] compiled for 1.12.2, module version = 0.4.2 [ 23.661] Module class: X.Org Video Driver [ 23.661] ABI class: X.Org Video Driver, version 12.0 [ 23.661] (II) ATI Proprietary Linux Driver Version Identifier:8.96.4 [ 23.661] (II) ATI Proprietary Linux Driver Release Identifier: 8.96.7 [ 23.661] (II) ATI Proprietary Linux Driver Build Date: Mar 12 2012 13:06:50 [ 23.661] (II) intel: Driver for Intel Integrated Graphics Chipsets: i810, i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM, 865G, 915G, E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM, Pineview G, 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35, Q33, GM45, 4 Series, G45/G43, Q45/Q43, G41, B43, B43, Clarkdale, Arrandale, Sandybridge Desktop (GT1), Sandybridge Desktop (GT2), Sandybridge Desktop (GT2+), Sandybridge Mobile (GT1), Sandybridge Mobile (GT2), Sandybridge Mobile (GT2+), Sandybridge Server, Ivybridge Mobile (GT1), Ivybridge Mobile (GT2), Ivybridge Desktop (GT1), Ivybridge Desktop (GT2), Ivybridge Server, Ivybridge Server (GT2) [ 23.661] (II) VESA: driver for VESA chipsets: vesa [ 23.661] (II) FBDEV: driver for framebuffer: fbdev [ 23.661] (++) using VT number 7 [ 23.661] (WW) xf86OpenConsole: setpgid failed: Operation not permitted [ 23.661] (WW) xf86OpenConsole: setsid failed: Operation not permitted [ 23.661] (WW) Falling back to old probe method for fglrx [ 23.661] (II) Loading PCS database from /etc/ati/amdpcsdb [ 23.661] (WW) Falling back to old probe method for vesa [ 23.661] (WW) Falling back to old probe method for fbdev [ 23.661] (EE) No devices detected. [ 23.661] Fatal server error: [ 23.661] no screens found [ 23.661] Please consult the The X.Org Foundation support at http://wiki.x.org for help. [ 23.661] Please also check the log file at "/var/log/Xorg.0.log" for additional information. [ 23.661] xorg.conf: cat /etc/X11/xorg.conf Section "ServerLayout" Identifier "aticonfig Layout" Screen 0 "aticonfig-Screen[0]-0" 0 0 EndSection Section "Module" Load "glx" EndSection Section "Monitor" Identifier "aticonfig-Monitor[0]-0" Option "VendorName" "ATI Proprietary Driver" Option "ModelName" "Generic Autodetecting Monitor" Option "DPMS" "true" EndSection Section "Device" Identifier "aticonfig-Device[0]-0" Driver "fglrx" BusID "PCI:1:0:0" EndSection Section "Screen" Identifier "aticonfig-Screen[0]-0" Device "aticonfig-Device[0]-0" Monitor "aticonfig-Monitor[0]-0" DefaultDepth 24 SubSection "Display" Viewport 0 0 Depth 24 EndSubSection EndSection Is there a way to get the Radeon to work in a hybrid configuration or to use the Radeon as an OpenCL only device?

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  • When module calling gets ugly

    - by Pete
    Has this ever happened to you? You've got a suite of well designed, single-responsibility modules, covered by unit tests. In any higher-level function you code, you are (95% of the code) simply taking output from one module and passing it as input to the next. Then, you notice this higher-level function has turned into a 100+ line script with multiple responsibilities. Here is the problem. It is difficult (impossible) to test that script. At least, it seems so. Do you agree? In my current project, all of the bugs came from this script. Further detail: each script represents a unique solution, or algorithm, formed by using different modules in different ways. Question: how can you remedy this situation? Knee-jerk answer: break the script up into single-responsibility modules. Comment on knee-jerk answer: it already is! Best answer I can come up with so far: create higher-level connector objects which "wire" modules together in particular ways (take output from one module, feed it as input to another module). Thus if our script was: FooInput fooIn = new FooInput(1, 2); FooOutput fooOutput = fooModule(fooIn); Double runtimevalue = getsomething(fooOutput.whatever); BarInput barIn = new BarInput( runtimevalue, fooOutput.someOtherValue); BarOutput barOut = barModule(BarIn); It would become with a connector: FooBarConnectionAlgo fooBarConnector = new fooBarConnector(fooModule, barModule); FooInput fooIn = new FooInput(1, 2); BarOutput barOut = fooBarConnector(fooIn); So the advantage is, besides hiding some code and making things clearer, we can test FooBarConnectionAlgo. I'm sure this situation comes up a lot. What do you do?

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  • Dot Net Nuke module works in "Edit" mode but not for "View": cache problem?

    - by Godeke
    I have a DNN task that simply runs some Javascript to compute a price based on a few input fields. This module works fine on our production site, but we had a company do a skin for us to improve the look of the site and the module fails under this new system. (DNN 05.06.00 (459) although it was 5.5 prior... I updated in a futile hope that it was a bug in the old revision.) What is incredibly odd about this is that the module works fine when I'm logged in to DNN and using the Edit mode as an administrator. In this case the small snippet of JavaScript loads fine and filling the fields results in a price. On the other hand it I click "View" (or more importantly, if I'm not logged in at all) the page loads a cached copy. Even odder, I have found the cache files in \Portals\2\Cache\Pages are generated and then only the cached data is being used. When the cached copy is loaded, the JavaScript doesn't appear (it is normally created via a Page.ClientScript.RegisterClientScriptBlock(). Additionally, the button which posts the data to the server doesn't execute any of the server side code (confirmed with a debugger) but instead just reloads the cached copy. If I manually delete the files in \Portals\2\Cache\Pages then everything works properly, but I have to do so after every page load: failing to do so simply loads the page as it was last generated repeatedly. Resetting the application (either via the UI or editing web.config) doesn't change this and clearing the cache from the Host Settings page doesn't actually clear these cached pages. I'm guessing that Edit mode bypasses the cache in some way, but I have gone as far as turning off all caching on the site (which is horrible for performance) and the cached version is still loaded. Has anyone seen anything like this? Shouldn't clearing the cache clear the files (I'm using the File provider for caching)? Shouldn't even a cached page go back to the server if the user posts back? EDIT: I should point out that permissions don't appear to be a problem on the cache directory... other pages cached output are deleted from this folder, just this page has this issue. EDIT 2: Clarifying some settings and conditions which I didn't provide. First, this module works fine in production under DNN 5.6.0. In our test environment with the consulting company's changes it fails (the changes are skin and page layout only in theory: the module source itself verifies as unchanged). All cache settings and the like have been verified the same between the two and we only resorted to setting the module cache to 0 and -1 (and disabling the test site's cache entirely) when we couldn't find another cause for the problem. I have watched the cache work correctly on many other pages in test: there is something about this page that is causing the problem. We have punted and are creating an installable skin based on the consultant's work as I suspect they have somehow corrupted the DNN install (database side I think).

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  • How can I build a generic dataset-handling Perl library?

    - by Pep.
    Hello, I want to build a generic Perl module for handling and analysing biomedical character separated datasets and which can, most certain, be used on any kind of datasets that contain a mixture of categorical (A,B,C,..) and continuous (1.2,3,881..) and identifier (XXX1,XXX2...). The plan is to have people initialize the module and then use some arguments to point to the data file(s), the place were the analysis reports should be placed and the structure of the data. By structure of data I mean which variable is in which place and its name/type. And this is where I need some enlightenment. I am baffled how to do this in a clean way. Obviously, having people create a simple schema file, be it XML or some other format would be the cleanest but maybe not all people enjoy doing something like this. The solutions I can think of are: Create a configuration file in XML or similar and with a prespecified format. Pass the information during initialization of the module. Use the first row of the data as headers and try to guess types (ouch) Surely there must be a "canonical" way of doing this that is also usable and efficient. Thanks p.

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  • How do I install mod_dav_svn module on an Apache / MAMP server?

    - by fettereddingoskidney
    How do I install additional modules into my server configuration? Currently all of the other modules are installed in /Applications/MAMP/Library/modules...and I see that they are mod_*.so source files, but I cannot seem to get mine to end up here... :? I am trying to set up an SVN repository and use my Apache (MAMP) server to serve the repository. I am using the subversion installation that came (pre-installed?) on Mac OS X 10.5. The repository is working, but I cannot access it remotely through my MAMP server using a client program (Dreamweaver CS5). When I try, I get an error from Dreamweaver, saying: Cannot connect to host xxx: Connection refused. This, I believe, is because I have not properly configured my Apache server to serve the svn repository. So, I added the following lines to my httpd.conf file: <Location /subversion> DAV svn SVNPath /Applications/MAMP/htdocs/svn/ AuthType Basic AuthName "Subversion repository" AuthUserFile /applications/mamp/htdocs/.htpasswd Require ServerAdmin </Location> Restarted the server with the command $ /Applications/MAMP/Library/bin/apachectl -k restart I used this path because otherwise the default apachectl path is set to /usr/sbin/apachectl, which is the location of the pre-installed command on Mac OS X, since the OS comes packaged with a built-in Apache server. And I get the error: Syntax error on line 1153 of /Applications/MAMP/conf/apache/httpd.conf: Unknown DAV provider: svn I checked the upper portion of httpd.conf and see that dav_module (mod_dav.so) is loaded and is in fact in my the modules directory of my server. However, mod_dav_svn is not installed in that directory nor is it in the LoadModule portion of httpd.conf. So I need to install it, right? I have tried installing modules into my MAMP server before but was never successful...because I don't know how to do it. Can someone please walk me through how to install that module? Thanks for your time!

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  • Perl CGI that sends a temporary loading page to client then later sends the actual results page

    - by Kurt W. Leucht
    I've wasted at least a half day of my company's time searching the Internet for an answer and I'm getting wrapped around the axle here. I can't figure out the difference between all the different technology choices (long polling, ajax streaming, comet, XMPP, etc.) and I can't get a simple hello world example working on my PC. I am running Apache 2.2 and ActivePerl 5.10.0. JavaScript is completely acceptable for this solution. All I want to do is write a simple Perl CGI script that when accessed, it immediately returns some HTML that tells the user to wait or maybe sends an animated GIF. Then without any user intervention (no mouse clicks or anything) I want the CGI script to at some time later replace the wait message or the animated GIF with the actual HTML results from their query. I know this is simple stuff and websites do it all the time, but I can't find a single working example that I can cut and paste onto my machine that will work. Here is my simple Hello World example that I've compiled from various Internet sources, but it doesn't seem to work. When I refresh this CGI URL in my web browser it prints nothing for 5 seconds, then it prints the PLEASE BE PATIENT web page, but not the results web page. What am I doing wrong? #!C:\Perl\bin\perl.exe use CGI; use CGI::Carp qw/fatalsToBrowser warningsToBrowser/; sub Create_HTML { my $html = <<EOHTML; <html> <head> <meta http-equiv="pragma" content="no-cache" /> <meta http-equiv="expires" content="-1" /> <script type="text/javascript" > var xmlhttp=false; /*@cc_on @*/ /*@if (@_jscript_version >= 5) // JScript gives us Conditional compilation, we can cope with old IE versions. // and security blocked creation of the objects. try { xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); } catch (E) { xmlhttp = false; } } @end @*/ if (!xmlhttp && typeof XMLHttpRequest!='undefined') { try { xmlhttp = new XMLHttpRequest(); } catch (e) { xmlhttp=false; } } if (!xmlhttp && window.createRequest) { try { xmlhttp = window.createRequest(); } catch (e) { xmlhttp=false; } } </script> <title>Ajax Streaming Connection Demo</title> </head> <body> Some header text. <p> <div id="response">PLEASE BE PATIENT</div> <p> Some footer text. </body> </html> EOHTML return $html; } my $cgi = new CGI; print $cgi->header; print Create_HTML(); sleep(5); print "<script type=\"text/javascript\">\n"; print "\$('response').innerHTML = 'Here are your results!';\n"; print "</script>\n";

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  • Building a regex builder

    - by i.h4d35
    I am a beginner in programming in general and web development in particular. I am especially bad at regular expressions. Recently I was involved in building a couple of cPanel plugins(Perl-CGI) and that's when I realized how bad I am in regex. As a result, I have decided to build an online regex builder - this will help me to learn regex and help other struggling with regex. I have checked out GSkinner, Rubular and a couple of others like regexpal. It seemed to be a little difficult to use, hence i thought of writing another one. I do not know which tool is best suited for the job. should I write it in Perl or Python? My skill level is between beginner and intermediate in both those languages. What would be a good starting point - building it for the CLI or for the browser? I plan to get a string as an input, ask if the user want to search or search and replace, enter the search string (and the replace string where applicable) and then generate a regex. Would this be the right way to go?

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  • What is the fastest way to pull a few element values out of XML files in Perl?

    - by Anon Guy
    I have a bunch of XML files that are about 1-2 megabytes in size. Actually, more than a bunch, there are millions. They're all well-formed and many are even validated against their schema (confirmed with libxml2). All were created by the same app, so they're in a consistent format (though this could theoretically change in the future). I want to check the values of one element in each file from within a Perl script. Speed is important (I'd like to take less than a second per file) and as noted I already know the files are well-formed. I am sorely tempted to simply 'open' the files in Perl and scan through until I see the element I am looking for, grab the value (which is near the start of the file), and close the file. On the other hand, I could use an XML parser (which might protect me from future changes to the XML formatting) but I suspect it will be slower than I'd like. Can anyone recommend an appropriate approach and/or parser? Thanks in advance.

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  • How do I handle a POST request in Perl and FastCGI?

    - by Peterim
    Unfortunately, I'm not familiar with Perl, so asking here. Actually I'm using FCGI with Perl. I need to 1. accept a POST request - 2. send it via POST to another url - 3. get results - 4. return results to the first POST request (4 steps). To accept a POST request (step 1) I use the following code (found it somewhere in the Internet): $ENV{'REQUEST_METHOD'} =~ tr/a-z/A-Z/; if ($ENV{'REQUEST_METHOD'} eq "POST") { read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'}); } else { print ("some error"); } @pairs = split(/&/, $buffer); foreach $pair (@pairs) { ($name, $value) = split(/=/, $pair); $value =~ tr/+/ /; $value =~ s/%(..)/pack("C", hex($1))/eg; $FORM{$name} = $value; } The content of $name (it's a string) is the result of the first step. Now I need to send $name via POST request to some_url (step 2) which returns me another result (step 3), which I have to return as a result to the very first POST request (step 4). Any help with this would be greatly appreciated. Thank you.

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  • How do I use Perl's WWW::Facebook::API to publish to a user's newsfeed?

    - by Russell C.
    We use Facebook Connect on our site in conjunction with the WWW::Facebook::API CPAN module to publish to our users newsfeed when requested by the user. So far we've been able to successfully update the user's status using the following code: use WWW::Facebook::API; my $facebook = WWW::Facebook::API->new( desktop => 0, api_key => $fb_api_key, secret => $fb_secret, session_key => $query->cookie($fb_api_key.'_session_key'), session_expires => $query->cookie($fb_api_key.'_expires'), session_uid => $query->cookie($fb_api_key.'_user') ); my $response = $facebook->stream->publish( message => qq|Test status message|, ); However, when we try to update the code above so we can publish newsfeed stories that include attachments and action links as specified in the Facebook API documentation for Stream.Publish, we have tried about 100 different ways without any success. According to the CPAN documentation all we should have to do is update our code to something like the following and pass the attachments & action links appropriately which doesn't seem to work: my $response = $facebook->stream->publish( message => qq|Test status message|, attachment => $json, action_links => [@links], ); For example, we are passing the above arguments as follows: $json = qq|{ 'name': 'i\'m bursting with joy', 'href': ' http://bit.ly/187gO1', 'caption': '{*actor*} rated the lolcat 5 stars', 'description': 'a funny looking cat', 'properties': { 'category': { 'text': 'humor', 'href': 'http://bit.ly/KYbaN'}, 'ratings': '5 stars' }, 'media': [{ 'type': 'image', 'src': 'http://icanhascheezburger.files.wordpress.com/2009/03/funny-pictures-your-cat-is-bursting-with-joy1.jpg', 'href': 'http://bit.ly/187gO1'}] }|; @links = ["{'text':'Link 1', 'href':'http://www.link1.com'}","{'text':'Link 2', 'href':'http://www.link2.com'}"]; The above, nor any of the other representations we tried seem to work. I'm hoping some other perl developer out there has this working and can explain how to create the attachment and action_links variables appropriately in Perl for posting to the Facebook news feed through WWW::Facebook::API. Thanks in advance for your help!

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  • Can I use POSIX signals in my Perl program to create event-driven programming?

    - by Shiftbit
    Is there any POSIX signals that I could utilize in my Perl program to create event-driven programming? Currently, I have multi-process program that is able to cross communicate but my parent thread is only able to listen to listen at one child at a time. foreach (@proc) { sysread(${$_}{'read'}, my $line, 100); #problem here chomp($line); print "Parent hears: $line\n"; } The problem is that the parent sits in a continual wait state until it receives it a signal from the first child before it can continue on. I am relying on 'pipe' for my intercommunication. My current solution is very similar to: http://stackoverflow.com/questions/2558098/how-can-i-use-pipe-to-facilitate-interprocess-communication-in-perl If possible I would like to rely on a $SIG{...} event or any non-CPAN solution. Update: As Jonathan Leffler mentioned, kill can be used to send a signal: kill USR1 = $$; # send myself a SIGUSR1 My solution will be to send a USR1 signal to my child process. This event tells the parent to listen to the particular child. child: kill USR1 => $parentPID if($customEvent); syswrite($parentPipe, $msg, $buffer); #select $parentPipe; print $parentPipe $msg; parent: $SIG{USR1} = { #get child pid? sysread($array[$pid]{'childPipe'}, $msg, $buffer); }; But how do I get my the source/child pid that signaled the parent? Have the child Identify itself in its message. What happens if two children signal USR1 at the same time?

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  • How can I remove HTML span tags with a Perl one liner?

    - by yaya3
    I want to perform the following vim substitution as a one-liner in the terminal with Perl. I would prefer to allow for any occurences of whitespace or newlines, rather than explicitly catering for them as I am below. %s/blockDontForget">\n*\s*<p><span><a\(.*\)<\/span>/blockDontForget"><p><a\1/g I've tried this: perl -pi -e 's/blockDontForget"><p><span><a(.*)<\/span>/blockDontForget"><p><a$1/msg' I presume I am misinterpreting the flags. Where am I going wrong? Thanks. EDIT: The above example is to strip the spans out of the following html: <div class="block blockDontForget"> <p><span><a href="../../../foo/bar/x/x.html">Lorem Ipsum</a></span></p> EDIT: It's just the <span>'s and </span>'s that are inbetween <p> and <a> from the "blockDontForget" class </div> that I want to remove (there are lots or these blockDontForget divs with spans inside anchors that I want to keep).

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  • Why can't I run a Perl program from TextMate?

    - by JZ
    I'm following a bioinformatics text, and this represents one of my first Perl scripts. While in TextMate, this does not produce any result. Is it functioning? I added "hello world" at the bottom and I don't see that when I run the script in TextMate. What have I done wrong? #!/usr/local/bin/perl -w use lib "/Users/fogonthedowns/myperllib"; use LWP::Simple; use strict; #Set base URL for all eutils my $utils = "http://eutils.ncbi.nlm.nih.gov/entrez/eutils"; my $db = "Pubmed"; my $query ="Cancer+Prostate"; my $retmax = 10; my $esearch = "$utils/esearch.fcgi?" . "db=$db&retmax=$retmax&term="; my $esearch_result = get($esearch.$query); print "ESEARCH RESULT: $esearch_result\n"; print "Using Query: \n$esearch$query\n"; print "hello world\n";

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