---
name: "Ns_ConnRead"
section: "3aolserver"
platform: "linux"
package: "aolserver4-dev"
version: "4.5.1-18.1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/Ns_ConnGets/3aolserver"
---

# Ns\_ConnRead(3aolserver)

Routines to copy connection content

Part of [Ns\_ConnGets(3aolserver)](/Ns_ConnGets/3aolserver.md).

```

```

## NAME

Ns\_ConnGets, Ns\_ConnRead, Ns\_ConnFlushHeaders, Ns\_ConnReadHeaders, Ns\_ConnReadLine - Routines to copy connection content

## SYNOPSIS

```
#include "ns.h"

char *
Ns_ConnGets(buf, bufsize, conn)

int
Ns_ConnFlushContent(conn)

int
Ns_ConnRead(conn, vbuf, toread)

int
Ns_ConnReadHeaders(conn, set, nreadPtr)

int
Ns_ConnReadLine(conn, dsPtr, nreadPtr)
```

## ARGUMENTS

- char *\*buf* (in)

  Pointer to string buffer of length *bufsize*.

- int *bufsize* (in)

  Length of buffer pointer to by *buf*.

- Ns\_Conn *conn* (in)

  Pointer to open connection.

- Ns\_DString *dsPtr* (out)

  Pointer to initialized dstring to receive copied line.

- int *\*nreadPtr* (out)

  Pointer to integer to receive number of bytes copied.

- Ns\_Set *set* (in/out)

  Pointer to initialized Ns\_Set to copy headers.

- int *toread* (in)

  Number of bytes to copy to location starting at *vbuf*

- void *\*vbuf* (in)

  Pointer to memory location to copy content.

  ```

  ```

## DESCRIPTION

These routines support copying content from the connection.  They all operate by copying from the content buffer returned by a call to **Ns\_ConnContent**, maintaining a private, shared offset into the content.  This means that these routines are not actually reading directly from the network and thus will not block waiting for input. See the man page on **Ns\_ConnContent** for details on how the content is pre-read by the server and how resources are managed for small and large content requests.

- char \***Ns\_ConnGets**(*buf, bufsize, conn*)

  Copies the next available line of text from the content to the given *buf* string, up to the given *bufsize* less space for a trailing null (\\0).  The result is a pointer to *buf* or NULL if an underlying call to **Ns\_ConnRead** fails.

- int **Ns\_ConnFlushContent**(*conn*)

  Performs a logical flush of the underlying content available to these routines.  It simply moves the private offset to the end of the content.  The result is NS\_OK unless an underlying call to **Ns\_ConnContent** failed in which case NS\_ERROR is returned.

- int **Ns\_ConnRead**(*conn, vbuf, toread*)

  Copies up to *toread* bytes from the content to the memory location pointed to by *vbuf*.  The result is the number of bytes copied which will match *toread* unless less bytes are available in the input or -1 if an underlying call to **Ns\_ConnContent** failed.

- int **Ns\_ConnReadHeaders**(*conn, set, nreadPtr*)

  Copies lines up to the first blank line or end of content up to the maximum header read size specified with the communication driver "maxheader" parameter (default: 32k).  Each line is parsed into "key: value" pairs into the given Ns\_Set pointed to be the *set* argument using the **Ns\_ParseHeader** routine with the *Ns\_HeaderCaseDisposition* specified by the "headercase" server option (default: Preserve).  The result is NS\_OK if all lines were consumed or NS\_ERROR on overflow beyond the max header limit or if there was an error with the underlying call to **Ns\_ConnRead** (including an error of a single line beyond the max line limit as described below).  The integer pointed to by the *nreadPtr* argument, if given, is updated with the total number of bytes consumed.  This routine can be useful when parsing multipart/form-data content to collect headers for each part.

- int **Ns\_ConnReadLine**(*conn, dsPtr, nreadPtr*)

  Copies the next available line to the given *dsPtr* dstring. The integer pointed to by *nreadPtr*, if present, is updated with the number of bytes copied.  The line will not include the trailing \\r\\n or \\n if present.  The function will return NS\_OK unless an underlying call to **Ns\_ConnContent** failed or the line exceeds the maximum line read size specified by the communication driver "maxline" parameter (default: 4k).  This routine differs from **Ns\_ConnGets** in that it copies the result to a dstring instead of a character buffer, requires a full 0or end-of-content terminated line, and enforces the maxline limit.

## SEE ALSO

[Ns\_ConnContent(3)](/Ns_ConnContent/3.md), [Ns\_ParseHeader(3)](/Ns_ParseHeader/3.md)

## KEYWORDS

connection, read, content