Listing and Counting Processes with a Certain Name

The -C option can be used with ps to display certain processes:
$ ps -C httpd
PID TTY TIME CMD
726 ? 00:00:00 httpd
732 ? 00:00:00 httpd
6064 ? 00:00:00 httpd
19452 ? 00:00:00 httpd
21047 ? 00:00:00 httpd
21048 ? 00:00:00 httpd
21049 ? 00:00:00 httpd
21060 ? 00:00:00 httpd
30127 ? 00:00:00 httpd
31629 ? 00:00:00 httpd
32380 ? 00:00:00 httpd
32381 ? 00:00:00 httpd
32620 ? 00:00:00 httpd
532 ? 00:00:00 httpd
533 ? 00:00:00 httpd
544 ? 00:00:00 httpd
1699 ? 00:00:00 httpd
1774 ? 00:00:00 httpd
2686 ? 00:00:00 httpd
3427 ? 00:00:00 httpd
3429 ? 00:00:00 httpd
3430 ? 00:00:00 httpd
12571 ? 00:00:00 httpd
12573 ? 00:00:00 httpd
12574 ? 00:00:00 httpd
$

Run this through wc to count the processes:

$ ps -C httpd h wc -l
24
$

The h option doesn't print the header, so the count is correct. The -l option for wc just prints the number of lines. Add this line to your .bashrc file to get an alias to count these processes:

alias ch="ps -C httpd h wc -l";

and you can then just type ch to count the httpd processes.