printf-debugging

As many young programmers do, I learned the usefulness of inserting numerous print-to-console statements of "here1," "here2," and so on at different points in code to figure out when my programs are going awry. This brute force debugging technique has saved me many, many times throughout my CS studies. However, when I started programming in C, I stumbled onto an interesting problem. If I were to try and run void* test; printf("hello world"); test[5] = 234; Of course I get a segfault for not malloc'ing memory for testChar. However, you would think logically that "hello world" would be printed

I have a bunch of printf debug helper macros and it would be pretty cool to have to not specify the type, is there anything you can do to allow something like macro overloading in c(can be gcc specific if its available in gcc 4.3). I thought maybe typeof but apparently that doesn't work. example macro(I also have some ascii terminal color stuff that I can't remember of the top of my head) #ifdef _DEBUG #define DPRINT_INT(x) printf("int %s is equal to %i at line %i",#x,x,__LINE__); . . . #else #define DPRINT_INT(x) . . . #endif Try this; it uses gcc's __builtin methods, and automatically

When I'm running a simple Ruby script, what's the easiest way to dump an object's fields to the console? I'm looking for something similar to PHP's print_r() that will work with arrays as well. Possibly: puts variable.inspect You might find a use for the methods method which returns an array of methods for an object. It's not the same as print_r , but still useful at times. >> "Hello".methods.sort => ["%", "*", "+", "<", "<<", "<=", "<=>", "==", "===", "=~", ">", ">=", "[]", "[]=", "__id__", "__send__", "all?", "any?", "between?", "capitalize", "capitalize!", "casecmp", "center", "chomp",

I have some bash scripts I have been running on Ubuntu 14.04 and 16.04 for well over a year now. Some recent Ubuntu update has broken bash and I cannot figure out how to sort this out. Example: #!/bin/bash INPUT=myinput.txt OUTPUT=myoutput.txt ACTION1="0;" cat $INPUT | while read LINE do printf "\t\"~${LINE}\"\t\t$ACTION1\n" >> $OUTPUT done my script then loops through the file doing the printf statement as follows but this is the output produced "~jetmo" 0; "~spamme" 0; "~baidu" 0; example contents of myinput.txt jetmon spammen baidu Input lines containing a lowercase n character gets

I'm sure it's a silly question to those who know, but I can't find an explanation of what it does or what it is. CSV.open('data.csv', 'r') do |row| p row end What does " p row " do? p() is a Kernel method It writes obj.inspect to the standard output. Because Object mixes in the Kernel module, the p() method is available everywhere. It's common, btw, to use it in poetry mode , meaning that the parens are dropped. The CSV snippet can be written like... CSV.open 'data.csv', 'r' do |row| p row end It's documented here with the rest of the Kernel module. Kernel#p is the little debugging brother of