php - preg_match() with backslashes doesn't work as expected / throws error -

i need preg_match() pattern in php , no matter errors.

i've looked on net , can't find tells me i'm doing wrong.

here's preg_match pattern:

preg_match('/\myapp\library\task\/', '\myapp\library\task\db\generate'); 

it returns array, do wrong? how can regex work properly?

i know sound crazy, need use 4 backslashes 1 backslash regex. code this:

preg_match('/\\\\myapp\\\\library\\\\task\\\\/', '\myapp\library\task\db\generate'); 

why need use 4? because in php use backslash escape following character, escape 1 literal backslash (\\).

but since are in regular expression need escape backslash if want backslash in regex, means have use \\ 2 backslashes php end in 1 escape other 2 backslashes end in 1 character, end single backslash in regex.