I want to install ffmpeg-php extension, but for that I need autoconf. So I've tried to install autoconf, but when I type ./configure this error is showed:
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether /bin/sh -n is known to work... yes
checking for expr... /usr/bin/expr
checking for GNU M4 that supports accurate traces... configure: error: no acceptable m4 could be found in $PATH.
GNU M4 1.4.5 or later is required; 1.4.11 is recommended
So, could somebody help me?