Handy cheats

[TOC]

the ASCII table

Source: http://www.in-ulm.de/~mascheck/various/ascii-tty/

    |  0 NUL|  1 SOH|  2 STX|  3 ETX|  4 EOT|  5 ENQ|  6 ACK|  7 BEL|
    |  8 BS |  9 HT | 10 NL | 11 VT | 12 NP | 13 CR | 14 SO | 15 SI |
    | 16 DLE| 17 DC1| 18 DC2| 19 DC3| 20 DC4| 21 NAK| 22 SYN| 23 ETB|
    | 24 CAN| 25 EM | 26 SUB| 27 ESC| 28 FS | 29 GS | 30 RS | 31 US |
     ===============================================================
    | 32 SP | 33  ! | 34  " | 35  # | 36  $ | 37  % | 38  & | 39  ' |
    | 40  ( | 41  ) | 42  * | 43  + | 44  , | 45  - | 46  . | 47  / |
    | 48  0 | 49  1 | 50  2 | 51  3 | 52  4 | 53  5 | 54  6 | 55  7 |
    | 56  8 | 57  9 | 58  : | 59  ; | 60  < | 61  = | 62  > | 63  ? |
     ---------------------------------------------------------------
    | 64  @ | 65  A | 66  B | 67  C | 68  D | 69  E | 70  F | 71  G |
    | 72  H | 73  I | 74  J | 75  K | 76  L | 77  M | 78  N | 79  O |
    | 80  P | 81  Q | 82  R | 83  S | 84  T | 85  U | 86  V | 87  W |
    | 88  X | 89  Y | 90  Z | 91  [ | 92  \ | 93  ] | 94  ^ | 95  _ |
     ---------------------------------------------------------------
    | 96  ` | 97  a | 98  b | 99  c |100  d |101  e |102  f |103  g |
    |104  h |105  i |106  j |107  k |108  l |109  m |110  n |111  o |
    |112  p |113  q |114  r |115  s |116  t |117  u |118  v |119  w |
    |120  x |121  y |122  z |123  { |124  | |125  } |126  ~ |127 DEL|

127 for DEL: all seven bits are set and originally a character on paper tape was “deleted” by just punching all holes

scripting: numerical and string comparison operators

	Perl		PHP		sh / bash		dash
	int	string	int	string	int	string	int	string
equal	=	eq	==	==	-eq	== (= with test-operator for POSIX complicance)	-eq	=
less then	<	lt	<	<	-lt	<	-lt	<

php elseif

CSS reminders

Pathetic but I keep forgetting this:
# = id

. = class

margin | border | padding | content | padding | border | margin

Image:

inline elements: a, em, strong, span
block-level element: div, h1…h6, p, ul, ol, li, table, tr, td, th, blockquote

html characters

format linux disk

fdisk /dev/sdX
n
p
1

t
L
83
w

fdisk -l
Device Boot Start End Blocks Id System
/dev/sdX1 1 10245 10490864 83 Linux

Format
———-
mkfs.ext4 -m0 /dev/sdX1
e2fsck -C 0 -f -y /dev/sdX1

Mount
——-
mount /dev/sdX1 /vol
vi /etc/fstab
/dev/sdX1 /vol ext4 defaults,relatime,auto,_netdev 0 0
or
/dev/sdX1 /vol ext4 defaults 0 0

create linux disk and loop mount

# dd if=/dev/zero of=/var/mydisk bs=1000 count=1000000
# losetup /dev/loop0
Used? Try /dev/loop1 etc., else
# losetup /dev/loop0 /var/mydisk
# mke2fs -t ext4 /dev/loop0
# mount /dev/loop0 /mnt
# df -h /mnt
Filesystem Size Used Avail Use% Mounted on
/dev/loop0 939M 18M 874M 2% /mnt
# umount /mnt
# mke2fs -t ext4 -m 0 /dev/loop0
# mount /dev/loop0 /mnt; df -h /mnt
Filesystem Size Used Avail Use% Mounted on
/dev/loop0 939M 18M 922M 2% /mnt
#

solaris

# dd if=/dev/zero of=/var/mydisk bs=1000 count=1000000
1000000+0 records in
1000000+0 records out
# lofiadm -a /var/mydisk /dev/lofi/1
# newfs /dev/lofi/1
newfs: construct a new file system /dev/rlofi/1: (y/n)? y
/dev/rlofi/1: 1953000 sectors in 3255 cylinders of 1 tracks, 600 sectors
953.6MB in 204 cyl groups (16 c/g, 4.69MB/g, 2240 i/g)
super-block backups (for fsck -F ufs -o b=#) at:
32, 9632, 19232, 28832, 38432, 48032, 57632, 67232, 76832, 86432,
1862432, 1872032, 1881632, 1891232, 1900832, 1910432, 1920032, 1929632,
1939232, 1948832
# mount /dev/lofi/1 /mnt
# df -h /mnt
Filesystem size used avail capacity Mounted on
/dev/lofi/1 895M 1.0M 840M 1% /mnt
#

init

add program: vi /etc/init.d/program; update-rc.d program start 91 2 3 4 5 . stop 09 0 1 6 .
remove program: update-rc.d -f program remove;rm /etc/init.d/program