What about Perl? What are the development prospects? What can you make up?

Perl language is a text analysis report language designed by Larry Wall, which is used for programming in Unix environment.

Development prospect: At present, only Japan, the United States and Britain are still developing large-scale websites in Perl language, among which Japan has the most job opportunities and can consider immigration.

Now PHO and JAVA are widely used in China. Perl, as a high-level language, is especially suitable for rapid development, especially rapid prototyping and tool development. Many projects may not use perl, but if you can use Perl, then you have a Swiss army knife more than others and can do some unexpected things.

Perl's strength lies in text processing, or as a "glue" between various programs, it has the characteristics of automatically identifying variables, can write dynamic web pages, and has a large number of plug-ins available. Perl is a complete programming language, and he can do what other programming languages can do (the complexity may be different).

Bioinformatics is widely used in text processing.

Extended data:

Perl programming skills

1, Perl timeout mechanism?

eval？

{?

my $ tmpCmd = " ping 192. 168.0 . 1 "；

local $ SIG { ALRM } = sub { alarm 0； Death "timeout"; };

Alarm (10); ?

my $ startCmdResult = qx($ tmpCmd)；

Alarm (0);

};

if ($@ =~ /TIMEOUT/)？

{

Print "ping timeout";

}

2. Ignore the SIGCHLD signal to avoid the zombie process.

$SIG{CHLD} =' ignore';

Step 3: Wait

Zixiu _ Hua

{

local $ | = 1；

my @progress_symbol = ('-'，' \\ '，' | '，'/')；

My $ n = 0；;

My $ count = 8；;

while(＄count-)

{

# print " \ r $ progress _ symbol[$ n]"；

$ n =($ n & gt； =3)? 0:$ n+ 1；

select(unde，unde，unde，0. 1)；

}

# print " \ r

local $ | = 0；

}

4.Perl multiline comments

Single line comments: marked with #.

Multi-line comments:

The most common method is to use POD(Plain Old Documentations) for multi-line annotation. The method is as follows:

=pod

Code to comment.

= cut

5, similar to the "document here" syntax in unix shell.

#! /usr/bin/perl -w

$ P = 3. 14 15926；

Print & lt& ltEOF

The price is 100 USD.

? Hello, world.

eof

6. The usage of 6.Perl constant

Use the constant PI = >(4* atan2( 1,1));

PI = 6； # pi cannot be modified; An error occurred.

Use the constant DEBUG = >? 1; ?

Print "pi equals", pi, "... \n" If debugging

Baidu encyclopedia -Perl language