perl 环境变量的设置

yangfeng@sbuild:~/RL73_gb_master$ cat test.pl 

#!/usr/bin/perl

system("export RL_BUILD_RELEASE=true");

print "RL_BUILD_RELEASE=$ENV{RL_BUILD_RELEASE}\n";

readpipe("export RL_BUILD_RELEASE=true");

print "RL_BUILD_RELEASE=$ENV{RL_BUILD_RELEASE}\n";

exec("export RL_BUILD_RELEASE=true");

print "RL_BUILD_RELEASE=$ENV{RL_BUILD_RELEASE}\n";

`export RL_BUILD_RELEASE=true`;

print "RL_BUILD_RELEASE=$ENV{RL_BUILD_RELEASE}\n";

$ENV{RL_BUILD_RELEASE}='true';

print "RL_BUILD_RELEASE=$ENV{RL_BUILD_RELEASE}\n";

yangfeng@sbuild:~/RL73_gb_master$ 

yangfeng@sbuild:~/RL73_gb_master$ 

yangfeng@sbuild:~/RL73_gb_master$ ./test.pl 

RL_BUILD_RELEASE=

RL_BUILD_RELEASE=

RL_BUILD_RELEASE=

RL_BUILD_RELEASE=

RL_BUILD_RELEASE=true