Oninit
Talk to an expert →

Informix Error -812: Cannot open pipe for output.

Cause and resolution

Cannot open pipe for output.

Under the Output option, you selected To-pipe and specified a program or command to receive the output. However, Informix SQL was unable to open the pipe to that program or command. Review the program or command that you typed to ensure that it is a syntactically valid UNIX or DOS command and that it names only programs that are in your current execution path. Also look for operating-system error messages; you might have exceeded a system quota on memory or processes.

Oninit® Troubleshooting Guidance

Reasons / Common Causes

-812 fires when the interactive tool's To-pipe output option can't open a pipe to the specified program/command — per the official guidance, a few possibilities: invalid command syntax, a program not in the execution path, or a system resource quota (memory/processes) exceeded.

  1. A syntactically invalid UNIX/DOS command specified for the pipe target, per the official guidance.
  2. A program named that isn't in the current execution path, per the official guidance — the shell/OS can't locate it to launch.
  3. A system quota on memory or processes exceeded, per the official guidance — an OS-level resource limit, not something wrong with the command itself.
Solutions / Resolution
  1. Review the program/command for valid syntax, per the official guidance.
  2. Confirm the named program is in the current execution path, per the official guidance:
    which the_program
  3. Check for OS-level error messages about exceeded memory/process quotas, per the official guidance, if the command itself looks correct.
Examples
Checking whether the program is in the execution path
$ which the_program
which: no the_program in (/usr/bin:/bin:/usr/local/bin)

Confirms the program isn't reachable via the current PATH — use its full path, or add its directory to PATH.

Diagnostic Checks
  1. Check the command's syntax and whether the named program is in the execution path.
  2. Check for OS-level resource-quota error messages if the command itself looks correct.
Related Errors / Related Topics
  • -811 — "Cannot open printer for output." A related output-destination error, for a printer device rather than a piped program.
  • -813 — "Cannot write to pipe for output (no reading process)." A related pipe-output error, about the pipe closing after it was successfully opened, rather than failing to open at all.

Confirm the command's syntax and that the program is in the execution path, then check for OS-level resource-quota messages.