peekfd - Man Page

peek at file descriptors of running processes

Synopsis

peekfd [-8,--eight-bit-clean] [-n,--no-headers] [-c,--follow] [-d,--duplicates-removed] [-V,--version] [-h,--help] pid [fd] [fd] ...

Description

peekfd attaches to a running process and intercepts all reads and writes to file descriptors.  You can specify the desired file descriptor numbers or dump all of them.

Options

-8

Do no post-processing on the bytes being read or written.

-n

Do not display headers indicating the source of the bytes dumped.

-c

Also dump the requested file descriptor activity in any new child processes that are created.

-d

Remove duplicate read/writes from the output.  If you're looking at a tty with echo, you might want this.

-v

Display a version string.

-h

Display a help message.

Files

/proc/*/fd

Not used but useful for the user to look at to get good file descriptor numbers.

Environment

None.

Diagnostics

The following diagnostics may be issued on stderr:

Error attaching to pid <PID>

An unknown error occurred while attempted to attach to a process, you may need to be root.

Bugs

Probably lots.  Don't be surprised if the process you are monitoring dies.

Author

Trent Waddington

See Also

ttysnoop(8)

Info

2021-12-01 psmisc