́ ́, ́ ́ (. branch instructions) , ( , , ).
(conditional brahch) (unconditional branch).
( ), . , , , jz (), jnz () () .
18.
( ) , , . . . , Perl Tcl , . ( sed grep), .
. ֳ () .
( ) , . ֳ , , . , , []. , , , , .
19. ѳ Grep
grep - egrep fgrep, grep. grep, .
$ Grep [ ] _
( ) , . grep , :
$ Grep - n variable *. [ ]
variable ѳ.
$ Grep From $ Mail
.
$ Grep From $ Mail | grep - v mary
, mary.
$ Grep - y mary $ HOME / lib / phone - book
|
|
|
mary.
- n , - v , - y ( ).
. grep : . , . , ed. , grep ( ) ed.
, , , * . ., , . , , , . , .
^ $ ' () ^ ($) .
,
$ Grep From $ MAIL
, From ,
$ Grep ' From ' $ MAIL
, From, , , . , grep .
grep , , : , [ az ] - . - grep ^, - , . , [^ 0-9] - , . , ] - , grep ed , , . , [] [-] .
'.' '?' : - . ( , , .)
:
$ Ls - l | grep '^ d'
$ Ls - l | grep '^ -. - Rw ' , .
'^ ' - ; ls - l - .
" " ('*') ( ), - . , x * x , [ a - zA - Z] - - , * x - x .
' .
-, 䳺 , xy * x, yy -, xyxyxy.
-, - , , , . , , , : [ a - zA - Z] [ a - zA - Z ] * (, ). . * ³ *, , . grep : . grep . , .
|
|
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,
$ Grep ' [: ] *:: ' / etc / password
: , - , , .
grep:
0 .
1 .
> 1 .
: . - , grep , 1, .
20. awk
Awk , . Awk . , , . Grep .
" AWK . , . , , . AWK -. AWK . , ."
Sed
sed ( . S tream ED itor) ( ), .
sed ( ), , sed- sed, .
sed . ³ . , , sed , . ' , sed .
sed ed, ' . , 25d ed 25 , sed 25, ( ) . ³ , sed. , sed , , . 25 76 (25t76) ed (25h; 76g) sed , , .
sort, uniq, join, cut, paste, split
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Sort
, , . SORT , .
Uniq
uniq Unix, , . (-) , . , . ﳿ , , . , , , , .
Cut
cut UNIX, .
(-b), (-c), (-f) (-d ). ij , : N, N-M, N- ( N ), -M ( M).
Paste
paste ( . paste ) Unix, : , , .
Split
split Unix, . ' . , ab, ( ). , , , xab .
23. Linux
Linux . ,
,
, (,
, , ). root,
Linux .
10 .
. ֳ
.
Linux -
( ,
).
ϳ
.
24. tc\.profile
/ etc / profile. ³ :
(umask)
,
profile . ҳ .
/ etc / profile:
#
unmask 022
#
MAIL = / usr / mail / $ LOGNAME
# / bin
PATH = / usr / bin:/ usr / sbin:/ etc::
#
TERM = lft
#
export MAIL PATH TERM
