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5.4.9 SYS_ISTTY (0x09)

Checks whether a file is connected to an interactive device.

Entry

On entry, r1 contains a pointer to a one-word argument block:

word 1 This is a handle for a previously opened file object.

Return

On exit, r0 contains:

• 1 if the handle identifies an interactive device

• 0 if the handle identifies a file

• a value other than 1 or 0 if an error occurs.

5.4.10 SYS_SEEK (0x0A)

Seeks to a specified position in a file using an offset specified from the start of the file.

The file is assumed to be a byte array and the offset is given in bytes.

Entry

On entry, r1 contains a pointer to a two-word data block:

word 1 This is a handle for a seekable file object.

word 2 This is the absolute byte position to be sought to.

Return

On exit, r0 contains:

• 0 if the request is successful

• A negative value if the request is not successful. SYS_ERRNO can be used to

read the value of the host

errno

variable describing the error.

Note

The effect of seeking outside the current extent of the file object is undefined.

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ARM VERSION 1.2 Scheda Tecnica Pagina 156