[PD] pd if statements

[vlada car]

hi,
can anyone tell me what help file i should use to find out something
about 'if' statements for PD.
i am getting some data via tcp and would need to use that in pd. the
print output looks like this:

tcp: 19:44:45 e

tcp: 19:44:45 r

tcp: 19:44:45 n

tcp: 19:44:45 b

and i need to use letters e r n b as numbers or as a bang function. so
these buttons( e r n b )
will trigger some processes.
so when i make 
|receive tcp| then |select e r n b| i get error: gatom: no method for '20:'
do i need to convert these values or translate them?

can somebody please help?
thanks
v