httpd(apache)の実体の場所を調べる方法

apacheの実体の場所を知る方法：

[kagen@home kagen]$ ps ax | grep httpd
1 ... - S ? 3:53 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 241:22 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 247:33 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:07 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:04 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:16 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:33 /usr/local/apache2.0.59/bin/httpd -f ...
1 ... - S ? 0:07 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:00 /usr/local/apache2.0.59/bin/httpd -f ...
5 ... - S ? 0:00 /usr/local/apache2.0.59/bin/httpd -f ...
0 ... schedu S pts/0 0:00 vim httpd.conf
0 ... pipe_w S pts/2 0:00 grep httpd

yuhei.kagayaさん、ありがとうございました。