Don’t get me wrong, please. I haven’t written these scripts — I was
merely using them.

Because I’ve got them lying ‘round in my so called “Web Dump”
for a long time now, I thought I’d write a slightly more comprehensive
introduction to what made my life easier just a little while ago.

I hope this can be of interest to some of you, and maybe I have a lucky
hand with keywords so that even more people can benefit from these nice
scripts when a search engine spider picks them up.

I have lsted these works in no particular order:

• default.theme: Default theme for light background colour terminals
• niq.pl: BitchX like tab completion, fixed version
• ircuwhois.pl: Format additional whois output from Undernet IRCd (ircu)
• messages_bottom.pl: Make chat start at the bottom of the window (by printing many newlines on window creation)
• trackbar.pl: Draw a line at the position where you last left the window
• dccrelay.pl: Redirect DCC sends
• mouse_soliton.pl: Script which can read xterm mouse sequences
• question.pl: Fake a dialog like question near the prompt

/*

Consider this following small example program.

*/
#include <functional>
#include <iostream>

using namespace std::placeholders;

/*

We write a subroutine that outputs the multiple of its arguments, a and b.

*/
void multiple(int a, int b, const std::string & who) {
  std::cout << who << ":\t" << a << "×" << b << "=" << a*b << std::endl;
}

int main() {
  /*

We then call it from main.

 */
  multiple(2,3,"direct");

  /*

Next, we want to use bind to bind some arguments and call it. Unsurprisingly, the output is the same.

 */
  std::bind(multiple,2,3,"bind")();

  /*

We can also store this bound function and call it:

 */
  auto bound(std::bind(multiple,2,3,"bound"));
  bound();

  /*

Things get wicked, when we want to predefine only one parameter, though :(

 */
  //std::bind(multiple,2,_1,"bindp")(3); // you wish!

To install perl modules without root permission, this seems to work for me within cpan:

UPDATE the modern recommendation would be to use the (almost) excellent local::lib module. First, download the archive through the link on the right side of the CPAN search page. Unpack it somewhere and follow the instructions on the CPAN site: run perl Makefile.PL --bootstrap and add the necessary call to your shell profile.

Now you can (after log-out and log-in) just run perl -MCPAN -Mlocal::lib -eshell and have it do auto-configuration (remove your .cpan/CPAN directory first if you have a broken configuration), and “install”ing packages should just work.

(old content below)

I wonder why this result isn’t on google’s #1 for int log2 gcc.

To get the integer logarithm to the base of 2, try

      sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(   n );
     sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(  n );
sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll( n ); 

If you look at automatic make file dependency rule generation for the g++ compiler, there are a lot of different solutions on the Internet. I’m not sure which one is the best, but it sure involved the -MM or -MMD switch to g++.

I found the following to work sufficiently at the end of my simple project Makefile:

.SUFFIXES: .d

.cpp.d:
	$(CXX) -MM -MT $@ -MT $(patsubst %.d,%.o,$@) $(CXXFLAGS) -o $@ $^

include $(patsubst %.cpp,%.d,$(SRC))

the include directive will make sure that the necessary name.d rule files are generated.

this requires the source files predefined in SRC, example:

SRC := $(wildcard *.cpp)

gdb backtrace looked something like this:

#0 0x00007ffff76a02e2 in __cxxabiv1::__vmi_class_type_info::__do_upcast
(__cxxabiv1::__class_type_info const*, void const*,
__cxxabiv1::__class_type_info::__upcast_result&) const () from /usr/lib64/libstdc++.so.6
#1 0x00007ffff769d4c5 in __cxxabiv1::__class_type_info::__do_upcast
(__cxxabiv1::__class_type_info const*, void**) const () from /usr/lib64/libstdc++.so.6
#2 0x00007ffff769e135 in get_adjusted_ptr(std::type_info const*, std::type_info const*, void**)
() from /usr/lib64/libstdc++.so.6
#3 0x00007ffff769e93c in __gxx_personality_v0 () from /usr/lib64/libstdc++.so.6
#4 0x00007ffff71dcfb3 in _Unwind_RaiseException () from /lib64/libgcc_s.so.1
#5 0x00007ffff769efc1 in __cxa_throw () from /usr/lib64/libstdc++.so.6
#6 0x00007ffff79a6ecb in void boost::throw_exception<boost::program_options::unknown_option>
(boost::program_options::unknown_option const&) () from ../boost_1_52_0/boost11/lib/
libboost_program_options.so.1.52.0
...
#10 0x00000000004098e4 in boost::program_options::parse_command_line (argc=2, argv=
0x7fffffffdaa8, desc=..., style=0, ext=...) at ./boost_includes/boost/program_options/detail/
parsers.hpp:125
#11 0x0000000000408e92 in main (argc=2, argv=0x7fffffffdaa8) at main.cpp:11

note to self: don’t forget to upgrade binutils/gold/ld

Usage scenario:

Your small group has a scanner in walking distance, and wants to use it for simple scanning.

• It is not worth it to connect the scanner to the user’s computer,

• and also not worth it to be running back and forth between scanner and computer to check the scanning progress (as is suggested by saned).

• Mixed local/network scanning on the machine is not required (as suggested in scanbd.)

• The scanner is connected to a machine without display but with audio hardware. In our case it is an old broken Thinkpad.

• Maybe the scanner is a cheap crappy scanner without automatic document feeding etc.

This script will poll the buttons, scan according to two pre-sets (you could make the scripts more complex if desired) and publish the result on a Windows share.

Communication with the user is done through speech synthesis software.

End user experience:

• The Windows share is added once through “Connect Network Drive” in Windows or as a smb:// Bookmark in Nautilus, possibly by a local “Computer Expert”

• User has something to scan, takes the papers to the room with the scanner. He puts each sheet on the scanner and pushes Button 1. When the scan is finished, he does the same with the next sheet and so on. At the end, the user pushes Button 4 to signal he is done scanning.

• User goes back to his computer, copies the finished PDF file out of the network share. If necessary, he launches Adobe or another software to fix up any rough edges in the scan.

• User could also print this document to some printer in yet another room, after reviewing that everything is in order.

Script to do it:

You can grab your copy here: scanbtn.tar. Detailed information is inside the README file therein. Enjoy!