Install PCRE by running the following commands: ./configure --prefix=/usr --enable-utf8 && make && make install If you reinstall grep after installing pcre, grep will get linked against pcre and may cause problems if /usr is a seperate mount point. To avoid this, either pass the option --disable-perl-regexp when executing ./configure for grep or move libpcre to /lib as follows. mv /usr/lib/libpcre.so.* /lib/ && ln -sf ../../lib/libpcre.so.0 /usr/lib/libpcre.so