Rename index.md -> README.md.

Author: cirosantilli

README.md

@@ -9,6 +9,11 @@ Important files:
 - [ubuntu/install.sh](ubuntu/install.sh): Ubuntu install methods many programs.
 - [utils.sh](utils.sh):                   dump of many utils that fit in no other category or are not large enough to get their own file. Many POSIX utilities.
 
+Documentation viewers:
+
+- [man.sh](man.sh)
+- [info.sh](info.sh)
+
 Base standards:
 
 - [linux.md](linux.md): Linux, LSB.
@@ -27,7 +32,6 @@ Initialization:
 
 Base topics:
 
-- [compile/](compile/):                       compilation process, dynamic libraries.
 - [desktop/](desktop/):                       X, XDG, GNOME, KDE and related utilities.
 - [filesystem.md](filesystem.md):             POSIX file permissions.
 - [file-permissions.md](file-permissions.md): filesystem, hard disks, mounting, partitions.
@@ -54,10 +58,16 @@ Generic data formats:
 
 [virtual-machine.md/](virtual-machine): Vagrant, Docker.
 
+Programming tools:
+
+- [compile/](compile/): compilation process, dynamic libraries.
+- [ack.sh](ack.sh)
+
 Related subjects in other repositories:
 
 - [networking](https://github.com/cirosantilli/net): networking tools and protocols: HTTP, SSH, curl Apache.
 
+
 #How to search for stuff
 
 If you know what you are searching for, use the following methods to search by keyword.

ack.sh

@@ -0,0 +1,68 @@
+# Like find and grep, but with some features specialized to programming,
+# and more convenient in general.
+
+# Nice filename/line/match highlight output.
+
+# Ignores .git .svn, backup, swap files by default.
+
+# Can detect and filter by filetype via extension and shebangs.
+
+## install
+
+    sudo aptitude install -y ack-grep
+  # `ack` package was already taken by a kanji converter!
+
+  # this begs for an alias:
+    alias ack="ack-grep"
+
+# Recursive find grep for perl_regex in python files only, detects shebangs:
+
+  ack --py perl_regex
+
+# Adds all python files git. shebang aware:
+
+  ack -f --py --print0 | xargs -0 -I '{}' git add '{}'
+
+# Print only include names in cpp files
+
+  ack --cc '#include\s+<(.*)>' --output '$1'
+
+# --sh for bash
+
+# `-k`: search in all known filetypes.
+
+# There seems to be no way to search into *all* files.
+# Well, we have GNU `grep -r` for that...
+
+## -f
+
+  # List all filenames of known types:
+
+    ack -f
+
+## -g
+
+  # List files of known types that match regex:
+
+    ack -g '\.py$'
+
+# Easter egg: bill the cat:
+
+  ack --thpppt
+
+## combos
+
+  # find lines in files:
+
+    ack -f | xargs grep 'find'
+
+  # dry run replace in files with regex::
+
+    ack -f | xargs -lne 'print if s/a/A/g'
+
+  # only prints modified lines
+
+  # non-dry run replace in files:
+
+    ack -f | xargs perl -pie 's/z/Z/g'
+

chat.sh

@@ -0,0 +1,146 @@
+# TODO convert to md.
+
+# Chat utilities, specially command line ones.
+
+##mseg write wall
+
+  # Write messages to other users on the system.
+
+  ##mseg
+
+    # Enable/disable messages:
+
+      mseg n
+      mseg
+        #n
+      mseg y
+      mseg
+        #y
+
+  ##write
+
+    # Write to a user in a TTY:
+
+      u=
+      write $u tty3
+
+    # Now:
+
+    # - type you message
+    # - type enter, and it is sent
+    # - hit Ctrl + D and its over
+
+      u=
+      h=
+      sudo write $h@$u tty2
+
+  ##wall
+
+    # Write to all:
+
+      wall
+
+    # Type you message. It is only sent after you ctrl+d
+
+    # Sends to all even if disabled:
+
+      sudo wall
+
+    # Play with it:
+
+      #go to tty3. on ubuntu: ctrl+alt+f3
+      #login as user u
+      mesg y
+      #go to tty7 (xserver). on ubuntu: ctrl+alt+f7
+      sudo write u tty3
+      #write
+      #go to tty3
+      #your message is there!
+
+##talk
+
+  # Commandline chat program.
+
+  # POSIX.
+
+    sudo aptitude install -y talk
+
+##IRC
+
+  #internet relay chat
+
+  #servers have channels
+
+  #log into a server, join a channel
+
+  #messages can be seen
+
+    #- by all people on channel
+    #- certain people you write to only
+
+  #you cannot see read old messages
+  #sent when you were not logged in!!
+
+  #it is also possible to send files to people
+
+  ##commands
+
+    #intro: <http://www.irchelp.org/irchelp/irctutorial.html>
+
+    #full list: <http://en.wikipedia.org/wiki/List_of_Internet_Relay_Chat_commands>
+
+    #/connect <server>
+
+    ##ubuntu channel
+
+        ##register
+
+          xdotool type "/msg nickserv register $password $email"
+
+        ##verify registration
+
+          #go to your email and get the registration code
+
+          regcode=
+          xdotool type "/msg nickserv verify register $uname $regcode"
+
+  ##clients
+
+    ##pidgin
+
+      #good because integrates with other ims
+
+      ##create account
+
+        #irc server + username on that server == a pidgin account
+
+        #add account > irc
+
+        #enter server username and pass
+
+      ##join/create channel:
+
+        #an irc channel == a pidgin chat
+
+        #chats appear on the buddy list like buddies
+
+        #buddies > join a chat > choose server, enter a #channel_name
+
+        #if you don't know the name and want to list the available channels,
+        #enter any #name, and then /list there
+
+        #a chat window appear, mapping to the chosen channel on chosen sever
+
+        #if you close the chat window, it will not be on your buddy list anymore
+
+      ##add channel to buddy list permanently:
+
+        #buddies > add a group. name it "irc".
+
+        #buddies > show > empty groups
+
+        #buddies > add a chat. choose type irc, server, channel.
+
+  ##irssi
+
+    #ncurses

compile/gcov.md

@@ -0,0 +1,7 @@
+GCC test coverage metrics.
+
+Must compile with `-ftest-coverate` to use:
+
+    gcc -Wall -fprofile-arcs -ftest-coverage cov.c
+
+TODO usage

compile/library.md

@@ -1,6 +1,6 @@
 To use a library you may need:
 
--   the compiled `.so` or `.a` 
+-   the compiled `.so` or `.a`
 
 -   for C and C++, the header `.h` file(s).
 
@@ -18,7 +18,7 @@ They have `.so` extension on Linux and `.dll` on windows
 
 Dynamic libraries are different from static libraries (`.o` and `.a`) static libraries are put inside the executable at compile time.
 
-Advantages and disadvantages of dynamic libraries over static libraries are the usual tradeoffs of share vs embbed design choices.
+Advantages and disadvantages of dynamic libraries over static libraries are the usual trade-offs of share vs embed design choices.
 
 Advantages:
 
@@ -46,7 +46,7 @@ Since the disadvantages are so minor, it is almost always better to use dynamic
 
 #Search path
 
-Find where gcc search path for both `.a` and `.so`:
+Find where GCC search path for both `.a` and `.so`:
 
     gcc -print-search-dirs | grep '^libraries' | tr ':' $'\n'
 
@@ -93,9 +93,9 @@ Standard: up to 3 numbers.
 
 Yes, they come after the `.so` otherwise there would be ambiguity: `liba.1.so` is version 1 of `liba` or simply `lib.a.1`?
 
-To link to a given version use full basename linking with verison number.
+To link to a given version use full basename linking with version number.
 
-linking takes care of version defaults:
+Linking takes care of version defaults:
 
 -   `liba.so.1.1.1`
 
@@ -157,15 +157,15 @@ How this information is represented is a part of the `.elf` format definition.
 
 ###What can be passed to -l
 
-The name given to -l must be either:
+The name given to `-l` must be either:
 
 -   stripped from `lib` and `.so` part
 
     Ex: `m`, for `libm.so`. *will not work for `libm.so.1` !!!!!
 
 -   colon + `:`full basename. Ex: `-l:libm.so.1`
 
-You need to compile like this so gcc can tell if all your functions are definied.
+You need to compile like this so GCC can tell if all your functions are defined.
 
 ###Relative vs absolute
 
@@ -243,15 +243,16 @@ View library load path:
 
     cat /etc/ld.so.conf
 
-Remember: after modifying this file, you must update the load file [cache][] or your changes will not be taken into effect.
+Remember: after modifying this file, you must update the load file cache
+or your changes will not be taken into effect.
 
 May also include other files by adding a line to that file:
 
     include /etc/ld.so.conf.d/*.conf
 
 This is done by default on Ubuntu.
 
-To take includes into consideration and print the actual search path, use ldconfig.
+To take includes into consideration and print the actual search path, use `ldconfig`.
 
 So you also need to look inside included files for the libraries:
 
@@ -338,7 +339,7 @@ Don't rely on this method for production.
 
 Program that loads shared libs for other programs.
 
-central part of the Linux system.
+Central part of the Linux system.
 
 This program links to no shared libs!
 

compression.md

@@ -167,6 +167,10 @@ Extract `a.gz` and erase it if successful:
 
     gzip -r .
 
+##gz file format
+
+IETF standardized format: <https://www.ietf.org/rfc/rfc1952.txt>
+
 ##Hardlinks
 
 ##Keep original