errinfo(1m)

errinfo1m

Print errno for syscall fails. uses dtrace.

Usage

errinfo [{-a | -A | -hsvZ}] [-c command]

Overview

errinfo snoops syscall failures and prints the errno value and description of the error number.

This program can help determine if applications are silently failing, providing some details on the cause.

Since this uses DTrace, only users with root privileges can run this command.

Options

-c

counts - print an aggregate style report containing a frequency count of errors

-p PID

examine this PID only

-n name

examine processes with ths name only (eg, "ls")

Examples

Default output, print errors as they occur,

# errinfo

Print a frequency count report,

# errinfo -c

Snoop errors as they occur for "ssh" processes,

# errinfo -n ssh PP

Snoop errors for PID 81 only,

# errinfo -p 81

Fields

EXEC

Program name (truncated)

SYSCALL

System call name

ERR

Value of errno

DESC

Description of errno message

Documentation

See the DTraceToolkit for further documentation under the Docs directory. The DTraceToolkit docs may include full worked examples with verbose descriptions explaining the output.

Exit

errinfo will run forever until Ctrl-C is hit.

Files

/usr/include/sys/errno.h

Contains the full descriptions for the error numbers.

Releases

115 releases since Mac OS X 10.5; the text changed 1 time.

  1. 10.5–10.5.8
  2. 10.6–26.5

Author

Brendan Gregg [Sydney, Australia]

From dtrace 413 in macOS 26.5. Parsed by carta from the page's man source.