Quickly locate process IDs by name to inspect, signal, or troubleshoot services using the pidof utility. 01.12.2025 | reading time: 2 min When a service misbehaves or a script needs a signal, the first task is to find the process ID; pidof does exactly that: type the program name and get one or more PIDs back, fast and script-friendly. A concrete demo Run the command and observe the output; here is a short session that finds nginx PIDs, requests a single PID, and shows the result code when a name is not found: ```bash $ pidof nginx 1234 1256 1300 $ pidof -s nginx 1234 $ pidof no-such-service $ echo $? 1 ``` Practical tips and caveats Use `pidof` when you know the executable name; it prints PIDs separated by spaces and returns success when any were found, non-zero when none exist; `-s` makes it return a single PID, `-x` helps match scripts or wrapper processes, and remember some systems restrict access to other users' /proc entries so root may be required to see every PID. When to reach for other commands If you need pattern matching across command lines use `pgrep`, if you want detailed process state use `ps` with the appropriate columns, and if the goal is to find which process holds a socket or file use `lsof`; combine tools when a single name is ambiguous or when more context is required. Next steps and practice Try `pidof` inside small scripts that check whether a daemon is running before starting it, practice excluding a PID in supervision scripts, and pair `pidof` with `kill` or `strace` during investigation; keep experimenting to build muscle memory and confidence. Wrap-up and a nudge pidof is a tiny, reliable tool that saves time when you need PIDs quickly; keep exploring process utilities and consider formalizing skills with certifications such as CompTIA Linux+ or LPIC-1 and focused exam preparation at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. processes utilities troubleshooting scripting
