---
name: "qio"
section: "3"
platform: "linux"
package: "inn"
version: "1:1.7.2q-52"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/qio"
---

# qio(3)

quick I/O part of InterNetNews library

## NAME

qio - quick I/O part of InterNetNews library

## SYNOPSIS

```
#include "qio.h"
QIOSTATE *
QIOopen(name, size)
    char	*name;
    int	size;
QIOSTATE *
QIOfdopen(fd, size)
    int	fd;
    int	size;
void
QIOclose(qp)
    QIOSTATE	*qp;
char *
QIOread(qp)
    QIOSTATE	*qp;
int
QIOlength(qp)
    QIOSTATE	*qp;
int
QIOtoolong(qp)
    QIOSTATE	*qp;
int
QIOerror(qp)
    QIOSTATE	*qp;
int
QIOtell(qp)
    QIOSTATE	*qp;
int
QIOrewind(qp)
    QIOSTATE	*qp;
int
QIOfileno(qp)
    QIOSTATE	*qp;
```

## DESCRIPTION

The routines described in this manual page are part of the InterNetNews library, [*libinn*(3)](/libinn/3.md). They are used to provide quick read access to files. The letters \`\`QIO'' stand for *Q*uick *I/O*.

*QIOopen* opens the file *name* for reading. It uses a buffer of *size* bytes, which must also be larger then the longest expected line. The header file defines the constant QIO\_BUFFER as a reasonable default. If *size* is zero, then *QIOopen* will call [*stat*(2)](/stat/2.md) and use the returned block size; if that fails it will use QIO\_BUFFER. It returns NULL on error, or a pointer to a handle to be used in other calls. *QIOfdopen* performs the same function except that *fd* refers to an already-open descriptor.

*QIOclose* closes the open file and releases any resources used by it.

*QIOread* returns a pointer to the next line in the file. The trailing newline will be replaced with a \\0. If EOF is reached, an error occurs, or if the line is longer than the buffer, *QIOread* returns NULL.

After a successful call to *QIOread*, *QIOlength* will return the length of the current line.

The functions *QIOtoolong* and *QIOerror* can be called after *QIOread* returns NULL to determine if there was an error, or if the line was too long. If *QIOtoolong* returns non-zero, then the current line did not fit in the buffer, and the next call to *QIOread* will try read the rest of the line. Long lines can only be discarded. If *QIOerror* returns non-zero, then a serious I/O error occurred.

*QIOtell* returns the [*lseek*(2)](/lseek/2.md) offset at which the next line will start.

*QIOrewind* sets the read pointer back to the beginning of the file.

*QIOfileno* returns the descriptor of the open file.

*QIOlength*, *QIOtoolong*, *QIOerror*, *QIOtell*, and *QIOfileno* are implemented as macro's defined in the header file.

## EXAMPLE

```
QIOSTATE	*h;
long	offset;
char	*p;
h = QIOopen("/etc/motd", QIO_BUFFER);
for (offset = QIOtell(h); (p = QIOread(h)) != NULL; offset = QIOtell(h))
    printf("At %ld, %s\n", offset, p);
if (QIOerror(h)) {
    perror("Read error");
    exit(1);
}
QIOclose(h);
```

## HISTORY

Written by Rich $alz \<rsalz@uunet.uu.net\> for InterNetNews. This is revision 1.7, dated 1993/01/29.