---
name: "pvm_setsbuf"
section: "3"
platform: "linux"
package: "pvm-dev"
version: "3.4.2-8"
release: "Debian 3.0 (Woody)"
platforms: ["linux"]
url: "https://new.carta.tech/pvm_setsbuf"
---

# pvm\_setsbuf(3)

Switches the active send buffer.

## NAME

pvm\_setsbuf - Switches the active send buffer.

## SYNOPSIS

```
C	int oldbuf = pvm_setsbuf( int bufid )
Fortran	call pvmfsetsbuf( bufid, oldbuf )
```

## PARAMETERS

- bufid

  **Integer the message buffer identifier for the new active send buffer.** **A value of 0 indicates the default receive buffer.**\

- oldbuf

  **Integer returning the message buffer identifier** **for the previous active send buffer.**

## DESCRIPTION

**The routine** *pvm\_setsbuf* **switches the active send buffer to** *bufid* **and saves the previous active send buffer** *oldbuf.* **If** *bufid* **is set to 0 then the present active send buffer** **is saved and no active send buffer exists.**

**The routine is required when managing multiple message buffers.** **For example switching back and forth between two buffers.** **One buffer could be used to send information to a graphical interface** **while a second buffer could be used send data to other tasks** **in the application.**

## EXAMPLES

```
C:
	sbuf1 = pvm_setsbuf( sbuf2 );
Fortran:
	CALL PVMFSETSBUF( NEWBUF, OLDBUF )
```

## ERRORS

**These error conditions can be returned by** *pvm\_setsbuf*

- PvmBadParam

  **giving an invalid bufid.**

- PvmNoSuchBuf

  **switching to a non-existent message buffer.**

## SEE ALSO

**pvm\_setrbuf(3PVM)**