Stderr Checking In Pipes (trypipeerr)
About 1 min
trypipeerr
)
Stderr Checking In Pipes (Checks state of each function in a pipeline and exits block on error
Description
trypipeerr
checks the state of each function and exits the block if any of them fail. Where trypipeerr
differs from regular tryerr
blocks is trypipeerr
will check every process along the pipeline as well as the terminating function (which tryerr
only validates against). The downside to this is that piped functions can no longer run in parallel.
Usage
trypipeerr { code-block } -> <stdout>
<stdin> -> trypipeerr { -> code-block } -> <stdout>
Examples
trypipeerr {
out "Hello, World!" -> grep: "non-existent string" -> cat
out "This command will be ignored"
}
Formated pager (less
) where the pager isn't called if the formatter (pretty
) fails (eg input isn't valid JSON):
func pless {
-> trypipeerr { -> pretty -> less }
}
Detail
A failure is determined by:
- Any process that returns a non-zero exit number
- Any process that returns more output via stderr than it does via stdout
You can see which run mode your functions are executing under via the fid-list
command.
See Also
- Caught Error Block (
catch
): Handles the exception code raised bytry
ortrypipe
- Disable Error Handling In Block (
unsafe
): Execute a block of code, always returning a zero exit number - Display Running Functions (
fid-list
): Lists all running functions within the current Murex session - Function / Module Defaults (
runmode
): Alter the scheduler's behaviour at higher scoping level - If Conditional (
if
): Conditional statement to execute different blocks of code depending on the result of the condition - Pipe Fail (
trypipe
): Checks for non-zero exits of each function in a pipeline - Schedulers: Overview of the different schedulers (or 'run modes') in Murex
- Stderr Checking In TTY (
tryerr
): Handles errors inside a block of code - Switch Conditional (
switch
): Blocks of cascading conditionals - Try Block (
try
): Handles non-zero exits inside a block of code
This document was generated from builtins/core/structs/tryerr_doc.yaml.