---
name: "getline"
section: "3"
platform: "macos"
package: "Libc"
version: "1752.120.2"
release: "macOS 26.5"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/getline"
---

# getline(3)

get a line from a stream

## NAME

**getdelim**, **getline** – get a line from a stream

## LIBRARY

Standard C Library (libc, -lc)

## SYNOPSIS

**#include \<stdio.h\>**

*ssize\_t*\

**getdelim**(*char \*\* restrict linep*, *size\_t \* restrict linecapp*, *int delimiter*,  *FILE \* restrict stream*);

*ssize\_t*\

**getline**(*char \*\* restrict linep*, *size\_t \* restrict linecapp*,  *FILE \* restrict stream*);

## DESCRIPTION

The **getdelim**() function reads a line from *stream*, delimited by the character *delimiter*. The **getline**() function is equivalent to **getdelim**() with the newline character as the delimiter. The delimiter character is included as part of the line, unless the end of the file is reached.

The caller may provide a pointer to a malloced buffer for the line in *\*linep*, and the capacity of that buffer in *\*linecapp*. These functions expand the buffer as needed, as if via **realloc**(). If *linep* points to a NULL pointer, a new buffer will be allocated. In either case, *\*linep* and *\*linecapp* will be updated accordingly.

## RETURN VALUES

The **getdelim**() and **getline**() functions return the number of characters written, excluding the terminating NUL character. The value -1 is returned if an error occurs, or if end-of-file is reached.

## EXAMPLES

The following code fragment reads lines from a file and writes them to standard output. The **fwrite**() function is used in case the line contains embedded NUL characters.

```
char *line = NULL;
size_t linecap = 0;
ssize_t linelen;
while ((linelen = getline(&line, &linecap, fp)) > 0)
	fwrite(line, linelen, 1, stdout);
```

## ERRORS

These functions may fail if:

- \[EINVAL\]

  Either *linep* or *linecapp* is NULL.

- \[EOVERFLOW\]

  No delimiter was found in the first SSIZE\_MAX characters.

These functions may also fail due to any of the errors specified for **fgets**() and **malloc**().

## SEE ALSO

[fgetln(3)](/fgetln/3.md), [fgets(3)](/fgets/3.md), [malloc(3)](/malloc/3.md)

## STANDARDS

The **getdelim**() and **getline**() functions conform to IEEE Std 1003.1-2008 (“POSIX.1”).

## HISTORY

These routines first appeared in FreeBSD 8.0.

## BUGS

There are no wide character versions of **getdelim**() or **getline**().