## luni, 31 martie 2014

### Arduino si telecomanda TV

Tutoriale arduino si IR sensor:
- IR Remote Signals
- IR Sensor
- Using an IR Sensor

## sâmbătă, 29 martie 2014

### Masina de paine

De curând am cumparat o masina de paine Moulinex. Tot ce pot sa spun este ca pâinea de casă este extraordinara si este cu mult mai bună decât cea din comerț.

Masina de paine Moulinex Homebread OW1101, 600W, 900g, 12 programe

Rețetă pâine neagră:
• 320 ml apa
• 2 lingurite rase de sare
• 3 masuri mari de ulei de măsline
• 1.5 masuri mici de  drojdie
• 550 g de faina , de preferat 100 g de faina alba si restul faina neagra
• 40 g de seminte de in
• opțional se mai poate adaugă și o linguriță de miere
Mod de preparare:
• Se amesteca 10 ml de apa (luata din cei 320 ml cântăriți) cu drojdia si cu mierea până se topesc si devine ca o crema mai subțire
• Se adaugă apa, sarea  și uleiul în cuva.
• Se cerne faina si se adauga in cuva. Faina trebuie cernuta pentru a se aera.
Programul folosit este numărul 3 cu grad de rumenire 2, iar semințele se adaugă atunci când se aude un bipait, după vreo oră. Rezultatul se vede mai jos și va asigura ca este o pâine delicioasă:

Poftă bună !

## vineri, 28 martie 2014

### What is fusion ?

Fusion is the process at the core of our Sun. What we see as light and feel as warmth is the result of a fusion reaction: hydrogen nuclei collide, fuse into heavier helium atoms and release tremendous amounts of energy in the process.The gravitational forces at play in the Universe have created the perfect conditions for fusion. Over billions of years, these forces caused the hydrogen clouds of the early Universe to gather into massive stellar bodies. In the extreme density and temperature of their cores, fusion occurs.

## How does fusion produce energy?

Atoms never rest: the hotter they are, the faster they move. In the core of our Sun, temperatures reach 15,000,000° Celsius. Hydrogen atoms are in a constant state of agitation, colliding at very great speeds. The natural electrostatic repulsion that exists between the positive charges of their nuclei is overcome, and the atoms fuse.  The fusion of light hydrogen atoms (H-H) produces a heavier element, helium.The mass of the resulting helium atom is not the exact sum of the two initial atoms, however—some mass has been lost and great amounts of energy have been gained. This is what Einstein's formula E=mc² describes: the tiny bit of lost mass (m), multiplied by the square of the speed of light (c²), results in a very large figure (E), which is the amount of energy created by a fusion reaction.Every second, our Sun turns 600 million tons of hydrogen into helium, releasing an enormous amount of energy. But without the benefit of gravitational forces at work in our Universe, achieving fusion on Earth has required a different approach.

Spor la studiat!

## miercuri, 26 martie 2014

### Cum se utilizeaza "grep/egrep/fgrep" ?

Utilitarul grep din Unix/Linux/Cygwin se folosește pentru a face căutări de text si de fisiere. Utilitarul are atât de multe opțiuni încât mi-e imposibil sa le acopăr pe toate. Va dau doar câteva exemple iar restul optiunilor va las pe voi sa le descoperiti.
Exemple:
grep "literal_string" filename
grep "string" FILE_PATTERN
grep -i "false" *.c - cauta cuvantul "false" case insensitive in toate fisierele c
grep "FALSE" *.* - cauta cuvantul "FALSE" case sensitive in toate fisierele c
grep -c "struct" *.h - cauta cuvantul "struct" in toate fisierele header h si afiseaza de cate ori a fost gasit


egrep '^(0|1)+ [a-zA-Z]+$' searchfile.txt match all lines in searchfile.txt which start with a non-empty bitstring, followed by a space, followed by a non-empty alphabetic word which ends the line egrep -c '^1|01$' lots_o_bits
- count the number of lines in lots_o_bits which either start with 1 or end with 01

egrep -c '10*10*10*10*10*10*10*10*10*10*1' lots_o_bits
- count the number of lines with at least eleven 1's

egrep -i '\' myletter.txt
- list all the lines in myletter.txt containing the word the insensitive of case.

Lista completa cu opțiuni le găsiți mai jos:
NAME
grep, egrep, fgrep - print lines matching a pattern

SYNOPSIS
grep [OPTIONS] PATTERN [FILE...]
grep [OPTIONS] [-e PATTERN | -f FILE] [FILE...]

DESCRIPTION
grep  searches  the named input FILEs (or standard input if no files are named, or if a single hyphen-minus (-) is given as file name) for lines
containing a match to the given PATTERN.  By default, grep prints the matching lines.

In addition, two variant programs egrep and fgrep are available.  egrep is the  same  as  grep -E.   fgrep  is  the  same  as  grep -F.   Direct
invocation as either egrep or fgrep is deprecated, but is provided to allow historical applications that rely on them to run unmodified.

OPTIONS
Generic Program Information
--help Print a usage message briefly summarizing these command-line options and the bug-reporting address, then exit.

-V, --version
Print the version number of grep to the standard output stream.  This version number should be included in all bug reports (see below).

Matcher Selection
-E, --extended-regexp
Interpret PATTERN as an extended regular expression (ERE, see below).  (-E is specified by POSIX.)

-F, --fixed-strings
Interpret PATTERN as a list of fixed strings, separated by newlines, any of which is to be matched.  (-F is specified by POSIX.)

-G, --basic-regexp
Interpret PATTERN as a basic regular expression (BRE, see below).  This is the default.

-P, --perl-regexp
Interpret PATTERN as a Perl regular expression.  This is highly experimental and grep -P may warn of unimplemented features.

Matching Control
-e PATTERN, --regexp=PATTERN
Use  PATTERN  as the pattern.  This can be used to specify multiple search patterns, or to protect a pattern beginning with a hyphen (-).
(-e is specified by POSIX.)

-f FILE, --file=FILE
Obtain patterns from FILE, one per line.  The empty file contains zero patterns, and therefore matches  nothing.   (-f  is  specified  by
POSIX.)

-i, --ignore-case
Ignore case distinctions in both the PATTERN and the input files.  (-i is specified by POSIX.)

-v, --invert-match
Invert the sense of matching, to select non-matching lines.  (-v is specified by POSIX.)

-w, --word-regexp
Select  only  those  lines  containing  matches  that  form  whole  words.  The test is that the matching substring must either be at the

-x, --line-regexp
Select only those matches that exactly match the whole line.  (-x is specified by POSIX.)

-y     Obsolete synonym for -i.

General Output Control
-c, --count
Suppress  normal  output;  instead  print a count of matching lines for each input file.  With the -v, --invert-match option (see below),
count non-matching lines.  (-c is specified by POSIX.)

--color[=WHEN], --colour[=WHEN]
Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers,  byte  offsets,  and  separators  (for
fields  and  groups  of  context  lines)  with  escape sequences to display them in color on the terminal.  The colors are defined by the
environment variable GREP_COLORS.  The deprecated environment variable GREP_COLOR is still supported,  but  its  setting  does  not  have
priority.  WHEN is never, always, or auto.

-L, --files-without-match
Suppress  normal  output;  instead print the name of each input file from which no output would normally have been printed.  The scanning
will stop on the first match.

-l, --files-with-matches
Suppress normal output; instead print the name of each input file from which output would normally have been printed.  The scanning  will
stop on the first match.  (-l is specified by POSIX.)

-m NUM, --max-count=NUM
Stop  reading  a  file  after NUM matching lines.  If the input is standard input from a regular file, and NUM matching lines are output,
grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless  of  the  presence  of
trailing  context  lines.   This  enables a calling process to resume a search.  When grep stops after NUM matching lines, it outputs any
trailing context lines.  When the -c or --count option is also used, grep does not output a count greater  than  NUM.   When  the  -v  or
--invert-match option is also used, grep stops after outputting NUM non-matching lines.

-o, --only-matching
Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line.

-q, --quiet, --silent
Quiet; do not write anything to standard output.  Exit immediately with zero status if any match is found, even if an error was detected.
Also see the -s or --no-messages option.  (-q is specified by POSIX.)

-s, --no-messages
Suppress error messages about nonexistent or unreadable files.  Portability note: unlike GNU grep, 7th Edition Unix grep did not  conform
to  POSIX,  because  it  lacked  -q and its -s option behaved like GNU grep's -q option.  USG-style grep also lacked -q but its -s option
behaved like GNU grep.  Portable shell scripts should avoid both -q and -s and should redirect standard and  error  output  to  /dev/null
instead.  (-s is specified by POSIX.)
Output Line Prefix Control
-b, --byte-offset
Print  the  0-based byte offset within the input file before each line of output.  If -o (--only-matching) is specified, print the offset
of the matching part itself.

-H, --with-filename
Print the file name for each match.  This is the default when there is more than one file to search.

-h, --no-filename
Suppress the prefixing of file names on output.  This is the default when there is only one file (or only standard input) to search.

--label=LABEL
Display input actually coming from standard input as input coming from file LABEL.  This is especially useful for tools like zgrep, e.g.,
gzip -cd foo.gz | grep --label=foo something

-n, --line-number
Prefix each line of output with the 1-based line number within its input file.  (-n is specified by POSIX.)

-T, --initial-tab
Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal.  This is useful
with options that prefix their output to the actual content: -H,-n, and -b.  In order to improve the probability that lines from a single
file  will  all  start  at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size
field width.

-u, --unix-byte-offsets
Report Unix-style byte offsets.  This switch causes grep to report byte offsets as if the file were a Unix-style text file, i.e., with CR
characters  stripped  off.   This  will produce results identical to running grep on a Unix machine.  This option has no effect unless -b
option is also used; it has no effect on platforms other than MS-DOS and MS-Windows.

-Z, --null
Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name.  For example, grep -lZ outputs a
zero  byte  after  each  file  name instead of the usual newline.  This option makes the output unambiguous, even in the presence of file
names containing unusual characters like newlines.  This option can be used with commands like find -print0, perl -0, sort -z, and  xargs
-0 to process arbitrary file names, even those that contain newline characters.

Context Line Control
-A NUM, --after-context=NUM
Print  NUM  lines of trailing context after matching lines.  Places a line containing a group separator (--) between contiguous groups of
matches.  With the -o or --only-matching option, this has no effect and a warning is given.

-B NUM, --before-context=NUM
Print NUM lines of leading context before matching lines.  Places a line containing a group separator (--) between contiguous  groups  of
matches.  With the -o or --only-matching option, this has no effect and a warning is given.

-C NUM, -NUM, --context=NUM
Print NUM lines of output context.  Places a line containing a group separator (--) between contiguous groups of matches.  With the -o or
--only-matching option, this has no effect and a warning is given.

File and Directory Selection
-a, --text
Process a binary file as if it were text; this is equivalent to the --binary-files=text option.

--binary-files=TYPE
If the first few bytes of a file indicate that the file contains binary data, assume that the file is of type TYPE.  By default, TYPE  is
binary,  and  grep  normally outputs either a one-line message saying that a binary file matches, or no message if there is no match.  If
TYPE is without-match, grep assumes that a binary file does not match; this is equivalent to the  -I  option.   If  TYPE  is  text,  grep
processes  a  binary file as if it were text; this is equivalent to the -a option.  Warning: grep --binary-files=text might output binary
garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands.

-D ACTION, --devices=ACTION
If an input file is a device, FIFO or socket, use ACTION to process it.  By default, ACTION is read, which means that  devices  are  read
just as if they were ordinary files.  If ACTION is skip, devices are silently skipped.

-d ACTION, --directories=ACTION
If  an input file is a directory, use ACTION to process it.  By default, ACTION is read, which means that directories are read just as if
they were ordinary files.  If ACTION is skip, directories are silently skipped.  If ACTION is recurse, grep reads all  files  under  each
directory, recursively; this is equivalent to the -r option.

--exclude=GLOB
Skip  files  whose  base  name  matches GLOB (using wildcard matching).  A file-name glob can use *, ?, and [...]  as wildcards, and \ to
quote a wildcard or backslash character literally.

--exclude-from=FILE
Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude).

--exclude-dir=DIR
Exclude directories matching the pattern DIR from recursive searches.

-I     Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option.

--include=GLOB
Search only files whose base name matches GLOB (using wildcard matching as described under --exclude).

-R, -r, --recursive
Other Options
--line-buffered
Use line buffering on output.  This can cause a performance penalty.

--mmap If possible, use the mmap(2) system call to read input, instead of the default read(2) system call.  In some  situations,  --mmap  yields
better  performance.   However,  --mmap  can  cause  undefined  behavior  (including  core  dumps) if an input file shrinks while grep is
operating, or if an I/O error occurs.

-U, --binary
Treat the file(s) as binary.  By default, under MS-DOS and MS-Windows, grep guesses the file type by looking at the contents of the first
32KB  read  from the file.  If grep decides the file is a text file, it strips the CR characters from the original file contents (to make
regular expressions with ^ and $work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat the input as a set of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands two different versions of regular expression syntax: "basic" and "extended." In GNU grep, there is no difference in available functionality using either syntax. In other implementations, basic regular expressions are less powerful. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list; if the first character of the list is the caret ^ then it matches any character not in the list. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means [0-9A-Za-z], except the latter form depends upon the C locale and the ASCII character encoding, whereas the former is independent of locale and character set. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign$ are meta-characters that respectively match the empty string at the beginning and end of a line.

The Backslash Character and Special Expressions
The symbols \< and \> respectively match the empty string at the beginning and end of a word.  The symbol \b matches the  empty  string  at  the
edge of a word, and \B matches the empty string provided it's not at the edge of a word.  The symbol \w is a synonym for [[:alnum:]] and \W is a
synonym for [^[:alnum:]].

Repetition
A regular expression may be followed by one of several repetition operators:
?      The preceding item is optional and matched at most once.
*      The preceding item will be matched zero or more times.
+      The preceding item will be matched one or more times.
{n}    The preceding item is matched exactly n times.
{n,}   The preceding item is matched n or more times.
{,m}   The preceding item is matched at most m times.
{n,m}  The preceding item is matched at least n times, but not more than m times.

Concatenation
Two regular expressions may be concatenated; the resulting regular expression matches any string formed by  concatenating  two  substrings  that
respectively match the concatenated expressions.

Alternation
Two  regular  expressions  may  be joined by the infix operator |; the resulting regular expression matches any string matching either alternate
expression.

Precedence
Repetition takes precedence over concatenation, which in turn takes precedence  over  alternation.   A  whole  expression  may  be  enclosed  in
parentheses to override these precedence rules and form a subexpression.

Back References and Subexpressions
The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular
expression.

Basic vs Extended Regular Expressions
In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions  \?,  \+,
\{, \|, $$, and$$.

Traditional egrep did not support the { meta-character, and some egrep implementations support \{ instead, so portable scripts should avoid { in
grep -E patterns and should use [{] to match a literal {.

GNU grep -E attempts to support traditional usage by assuming that {  is  not  special  if  it  would  be  the  start  of  an  invalid  interval
specification.   For  example,  the  command  grep -E '{1'  searches  for the two-character string {1 instead of reporting a syntax error in the
regular expression.  POSIX.2 allows this behavior as an extension, but portable scripts should avoid it.
ENVIRONMENT VARIABLES
The behavior of grep is affected by the following environment variables.

The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in  that  order.   The  first  of
these  variables  that  is  set  specifies  the  locale.  For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian
Portuguese locale is used for the LC_MESSAGES category.  The C locale is used if none of these environment variables  are  set,  if  the  locale
catalog is not installed, or if grep was not compiled with national language support (NLS).

GREP_OPTIONS
This  variable  specifies  default  options  to  be  placed in front of any explicit options.  For example, if GREP_OPTIONS is '--binary-
files=without-match --directories=skip', grep behaves as if the two options --binary-files=without-match and --directories=skip had  been
specified before any explicit options.  Option specifications are separated by whitespace.  A backslash escapes the next character, so it
can be used to specify an option containing whitespace or a backslash.

GREP_COLOR
This variable specifies the color used to highlight matched (non-empty) text.  It is  deprecated  in  favor  of  GREP_COLORS,  but  still
supported.   The  mt,  ms, and mc capabilities of GREP_COLORS have priority over it.  It can only specify the color used to highlight the
matching non-empty text in any matching line (a selected line when the -v command-line option is omitted, or a context line  when  -v  is
specified).  The default is 01;31, which means a bold red foreground text on the terminal's default background.

GREP_COLORS
Specifies  the  colors  and  other  attributes  used  to  highlight  various parts of the output.  Its value is a colon-separated list of
capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean  capabilities  omitted  (i.e.,
false).  Supported capabilities are as follows.

sl=    SGR  substring  for  whole  selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines
when -v is specified).  If however the boolean rv capability and the -v command-line option are  both  specified,  it  applies  to
context matching lines instead.  The default is empty (i.e., the terminal's default color pair).

cx=    SGR substring for whole context lines (i.e., non-matching lines when the -v command-line option is omitted, or matching lines when
-v is specified).  If however the boolean rv capability and the -v command-line option are both specified, it applies to  selected
non-matching lines instead.  The default is empty (i.e., the terminal's default color pair).

rv     Boolean  value  that  reverses  (swaps) the meanings of the sl= and cx= capabilities when the -v command-line option is specified.
The default is false (i.e., the capability is omitted).

mt=01;31
SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is  omitted,
or  a  context line when -v is specified).  Setting this is equivalent to setting both ms= and mc= at once to the same value.  The
default is a bold red text foreground over the current line background.

ms=01;31
SGR substring for matching non-empty text in a selected line.  (This is only used when the -v  command-line  option  is  omitted.)
The effect of the sl= (or cx= if rv) capability remains active when this kicks in.  The default is a bold red text foreground over
the current line background.

mc=01;31
SGR substring for matching non-empty text in a context line.  (This is only used when the -v command-line  option  is  specified.)
The effect of the cx= (or sl= if rv) capability remains active when this kicks in.  The default is a bold red text foreground over
the current line background.

fn=35  SGR substring for file names prefixing any content line.  The default is a magenta text foreground  over  the  terminal's  default
background.
ln=32  SGR  substring  for  line  numbers prefixing any content line.  The default is a green text foreground over the terminal's default
background.

bn=32  SGR substring for byte offsets prefixing any content line.  The default is a green text foreground  over  the  terminal's  default
background.

se=36  SGR  substring  for  separators  that are inserted between selected line fields (:), between context line fields, (-), and between
groups of adjacent lines when nonzero context is specified (--).  The default is  a  cyan  text  foreground  over  the  terminal's
default background.

ne     Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends.
This is needed on terminals on which EL is not supported.  It is otherwise useful on  terminals  for  which  the  back_color_erase
(bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too
slow or causes too much flicker.  The default is false (i.e., the capability is omitted).

Note that boolean capabilities have no =...  part.  They are omitted (i.e., false) by default and become true when specified.

See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used  for  permitted  values  and  their
meaning  as character attributes.  These substring values are integers in decimal representation and can be concatenated with semicolons.
grep takes care of assembling the result into a complete SGR sequence (\33[...m).  Common values to concatenate include 1 for bold, 4 for
underline,  5  for  blink,  7  for  inverse,  39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode
foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to  47  for
background  colors,  100  to  107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background
colors.

LC_ALL, LC_COLLATE, LANG
These variables specify the locale for the LC_COLLATE  category,  which  determines  the  collating  sequence  used  to  interpret  range
expressions like [a-z].

LC_ALL, LC_CTYPE, LANG
These  variables  specify  the  locale  for  the  LC_CTYPE  category, which determines the type of characters, e.g., which characters are
whitespace.

LC_ALL, LC_MESSAGES, LANG
These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages.  The  default
C locale uses American English messages.

POSIXLY_CORRECT
If  set,  grep  behaves  as  POSIX.2  requires; otherwise, grep behaves more like other GNU programs.  POSIX.2 requires that options that
follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and  are  treated
as  options.   Also,  POSIX.2 requires that unrecognized options be diagnosed as "illegal", but since they are not really against the law
the default is to diagnose them as "invalid".  POSIXLY_CORRECT also disables _N_GNU_nonoption_argv_flags_, described below.

_N_GNU_nonoption_argv_flags_
(Here N is grep's numeric process ID.)  If the ith character of this environment variable's value is 1, do not consider the  ith  operand
of  grep  to  be  an  option,  even  if it appears to be one.  A shell can put this variable in the environment for each command it runs,
specifying which operands are the results of file name wildcard expansion and therefore should not be treated as options.  This  behavior
is available only with the GNU C library, and only when POSIXLY_CORRECT is not set.

EXIT STATUS
Normally,  the  exit  status  is 0 if selected lines are found and 1 otherwise.  But the exit status is 2 if an error occurred, unless the -q or
--quiet or --silent option is used and a selected line is found.  Note, however, that POSIX only mandates, for programs such as grep,  cmp,  and
diff,  that  the exit status in case of error be greater than 1; it is therefore advisable, for the sake of portability, to use logic that tests
for this general condition instead of strict equality with 2.

Copyright ▒ 1998, 1999, 2000, 2002, 2005 Free Software Foundation, Inc.

This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS  FOR  A  PARTICULAR
PURPOSE.

BUGS
Reporting Bugs
Email bug reports to , a mailing list whose web page is .  grep's Savannah bug
tracker is located at .

Known Bugs
Large repetition counts in the {n,m} construct may cause grep to use lots of memory.  In addition, certain  other  obscure  regular  expressions
require exponential time and space, and may cause grep to run out of memory.

Back-references are very slow, and may require exponential time.

Regular Manual Pages
awk(1), cmp(1), diff(1), find(1), gzip(1), perl(1), sed(1), sort(1), xargs(1), zgrep(1), mmap(2), read(2), pcre(3), pcrepattern(3), terminfo(5),
glob(7), regex(7).

POSIX Programmer's Manual Page
grep(1p).

TeXinfo Documentation
The full documentation for grep is maintained as a TeXinfo manual.  If the info and grep programs are  properly  installed  at  your  site,  the
command

info grep



### Sistemele de operare folosite in lume la ora actuala

E cam șocant .... Windows conduce detașat :(
Ma așteptam sa apară și Ubuntu ... cred ca e la secțiunea "others". Trist!
Statistica e de aici Statcounter.com .. O zi plăcută tuturor.