---
name: "explain_setvbuf_or_die"
section: "3"
platform: "linux"
package: "libexplain-dev"
version: "1.4.D001-16"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/explain_setvbuf_or_die"
---

# explain\_setvbuf\_or\_die(3)

stream buffering operations and report errors

## NAME

explain\_setvbuf\_or\_die - stream buffering operations and report errors

## SYNOPSIS

\#include \<libexplain/setvbuf.h\>

void explain\_setvbuf\_or\_die(FILE \*fp, char \*data, int mode, size\_t size);\
 int explain\_setvbuf\_on\_error(FILE \*fp, char \*data, int mode, size\_t size);

## DESCRIPTION

The **explain\_setvbuf\_or\_die** function is used to call the [*setvbuf*(3)](/setvbuf/3.md) system call. On failure an explanation will be printed to *stderr*, obtained from the [*explain\_setvbuf*(3)](/explain_setvbuf/3.md) function, and then the process terminates by calling `exit(EXIT_FAILURE)`.

The **explain\_setvbuf\_on\_error** function is used to call the [*setvbuf*(3)](/setvbuf/3.md) system call. On failure an explanation will be printed to *stderr*, obtained from the [*explain\_setvbuf*(3)](/explain_setvbuf/3.md) function, but still returns to the caller.

- *fp*

  The fp, exactly as to be passed to the [*setvbuf*(3)](/setvbuf/3.md) system call.

- *data*

  The data, exactly as to be passed to the [*setvbuf*(3)](/setvbuf/3.md) system call.

- *mode*

  The mode, exactly as to be passed to the [*setvbuf*(3)](/setvbuf/3.md) system call.

- *size*

  The size, exactly as to be passed to the [*setvbuf*(3)](/setvbuf/3.md) system call.

## RETURN VALUE

The **explain\_setvbuf\_or\_die** function only returns on success, see [*setvbuf*(3)](/setvbuf/3.md) for more information. On failure, prints an explanation and exits, it does not return.

The **explain\_setvbuf\_on\_error** function always returns the value return by the wrapped [*setvbuf*(3)](/setvbuf/3.md) system call.

## EXAMPLE

The **explain\_setvbuf\_or\_die** function is intended to be used in a fashion similar to the following example:

```
explain_setvbuf_or_die(fp, data, mode, size);
```

## SEE ALSO

- [*setvbuf*(3)](/setvbuf/3.md)

  stream buffering operations

- [*explain\_setvbuf*(3)](/explain_setvbuf/3.md)

  explain [*setvbuf*(3)](/setvbuf/3.md) errors

- [*exit*(2)](/exit/2.md)

  terminate the calling process

## COPYRIGHT

libexplain version 1.4\
 Copyright (C) 2010 Peter Miller