There is a simple Linux utility for counting characters, lines and words in files called wc. This allows you to give a file as an argument or a stream and get the counts of the aforementioned items.

wc <filename>

or

cat <filename> | wc

The options that wc accepts

-c,–bytes	print the byte counts
-m,–chars	print the character counts
-l,–lines	print the line counts
-L,–max-line-length	print the length of the longest line
-w,–words	print the word counts

The ouput with no arguments will be three numbers (words,lines,characters. Otherwise the the number will reflect the argument you have passed.

And if you pass multiple filenames the output displays counts for all files and totals.

 >wc -l HelloWorld.java sample.txt
    8 HelloWorld.java
   25 sample.txt
   33 total

I regularly have to find where a file is located and usually use find:

find . | grep 

Where is replaced with the filename or partial name to match. So I finally decided to write a script to just run this and allow me to print the matching names and even potentially pass the -i flag to grep.

#!/bin/sh


if [ $# -lt 1 ]; then
  echo 1>&2 Usage: $0 ""
  exit 127
fi
icase=

while [ $# -ge 1 ]; do
   case $1 in
     -i)  icase=$1;;
      *)  search=$1 ;;
   esac
   shift
done

find .  | grep $icase $search

This is just a simple script which I have named ffind that searches starting from the current directory. This lets me search with the following commands:

ffind bak$

This will search for all files that end with “bak” .

ffind -i edr

This will search for all files with “edr” regardless of case

I have been searching through source code and files for years. And I used to use find with a few arguments to get what I was looking for.

find . -exec grep  {} ; -print

I used the -print after the exec arguments to show the file only when the grep succeeded.  This worked but was a bit to type each time I used it. So I came up with a little script that would help me to search for the an argument and even allow a case insensitive search as well.
 

#!/bin/sh

if [ $# -lt 1 ]; then
  echo 1>&2 Usage: $0 ""
  exit 127
fi
icase=
search=

while [ $# -ge 1 ]; do
  case $1 in 
     -i) icase=$1;;
      *) search=$1 ;;
  esac
  shift
done

find . -type f -print0 | xargs -0 grep $icase $search

The script takes at least one argument and excepts a ‘-i’ argument to make grep use a case insensitive search. This will print the file name and the line that matches the search term. It can be easily adapted to show the count of matched patterns (‘-c’) or the line number (‘-n’).

Here is a list of the Hello World Programs for different languages:

C

#include <stdio.h>
int main()
{
printf("Hello World!");
}

C++

#include <iostream.h>
int main()
{
cout << "Hello World!" << endl;
}

C#

public class HelloWorld
  public static void Main()
  {
    System.Console.WriteLine("Hello World!");
  }

Java

class HelloWorld {
static void main(String[] args)
{
System.out.println("Hello World!");
}

SHELL

echo "Hello World"

Python 2

print "Hello World!\n"

Python 3

print ("Hello World!")

Ruby

puts "Hello World!"

Perl

print "Hello World!n";

PHP

  <?php      
    print "Hello World!";
  ?>

Rust

fn main() {
    println("Hello World!");
}

This is the simplest form of Hello World for most of these languages.