Description

Sed is a very complex program which has many commands. It is a important Unix/Linux tool. we implement a few of the most important commands of sed. Speed is a POSIX-compatible subset of sed with extended regular expressions (EREs). The Speed is implemented in Perl

Supported Command 1

requirement

• speel.pl will be given a single Speed command as a command-line argument.
• The Speed command will be one of 'q', 'p', 'd', or 's'. The only other command-line argument possible is the -n option.
• speed.pl need only read from standard input.
• Speed command can optionally be preceded by an address specifying the line(s) they apply to. This address can either be line number or a regex. line number is a positive number and regex is delimited with slash / characters

q - quit command

The Speed q command causes speed.pl to exit
example:
seq 500 600 | ./speed.pl '/^.+5$/q'
500
501
502
503
504
505

p - print command

The Speed p commands prints the input line
example:
seq 7 11 | ./speed.pl '4p' 7
8
9
10
10
11

d - delete command

The Speed d commands deletes the input line
example:
seq 11 20 | ./speed.pl '/[2468]/d'
11
13
15
17
19

s - substitute command

The Speed s command replaces the specified regex on the input line. The substitute command can followed optionally by the modifier character g
example:
seq 1 5 | ./speed.pl 's/[15]/zzz/'
zzz
2
3
4
zzz

-n command line option

The Speed -n command line option stops input lines being printed by default. -n command line option is the only useful in conjunction with the p command.
example:
seq 2 3 20 | ./speed.pl -n '/^1/p'
11
14
17

Supported Command 2

requirement

• In additional to the previous requirement, $ can be used as an address.
• Speed commands can optionally be preceded by a comma separated pair of address specifying the start and finish of the range of lines the command applies to.
• substitue regex are not always delimited with slash / characters. whatever the delimiter is, it will not appear in regexes.

s - substitute command

any non-whitespace character may be used to delimit a substitute command
example:
seq 1 5 | ./speed.pl 's?[15]?zzz?'
zzz
2
3
4

multiple command

multiple Speed commands can be supplied separated by semicolons ; or newlines
example:
seq 1 20 | ./speed.pl '/2$/,/8$/d;4,6p'
1
9
10
11
19
20

Language

Perl

How to use

clone the speed.pl to the local computer and use as filter terminal command like example