regex - User defined Regular expression pattern match, how to? -

i got complicated file having contents as:

original file

aaa {         "(bbb|kkk)"   {     b_1 abc;     b_2 bcd;     b_3 efg;     b_4 xyz;   }    ccc   {     c_1 cbc;     c_2 dcd;   } }  ddd {    eee   {     e_1 ebc;     e_2 fcd;   }    "(fff|lll|mmm|nnn)"   {     f_1 gbc;     f_2 hcd;   } }  ggg {   g_1 ibc; }  hhh {   iii   {     jjj     {       j_1 jbc;       j_2 kbc;     }   } } 

i want using awk or tools output (just take example)

f_1 = gbc g_1 = ibc j_1 = jbc 

my question is: how define regular expression pattern match, first, search key word fff, output contents between closest bracelets { , }?

f_1 gbc; f_2 hcd; 

and contents can further piped , using grep can value gbc item f_1.

anyone knows how it?

this allow "define regular expression pattern match, first, search key word fff, output contents between closest bracelets { , }":

$ gawk -v rs='\0' '{ print gensub(/.*\yfff\y[^{]+{[[:space:]]*\n([^}]+)\n[[:space:]]*}.*/,"\\1","") }' file     f_1 gbc;     f_2 hcd; 

do not pipe output grep. whatever want can done within single awk call.