shmat.2freebsd

Langue: en

Version: 265821 (debian - 07/07/09)

Section: 2 (Appels système)


BSD mandoc

NAME

shmat shmdt - attach or detach shared memory

LIBRARY

Lb libc

SYNOPSIS

In machine/param.h In sys/types.h In sys/ipc.h In sys/shm.h Ft void * Fn shmat int shmid const void *addr int flag Ft int Fn shmdt const void *addr

DESCRIPTION

The Fn shmat system call attaches the shared memory segment identified by Fa shmid to the calling process's address space. The address where the segment is attached is determined as follows:

The Fn shmdt system call detaches the shared memory segment at the address specified by Fa addr from the calling process's address space.

RETURN VALUES

Upon success, Fn shmat returns the address where the segment is attached; otherwise, -1 is returned and errno is set to indicate the error.

Rv -std shmdt

ERRORS

The Fn shmat system call will fail if:
Bq Er EINVAL
No shared memory segment was found corresponding to Fa shmid .
Bq Er EINVAL
The Fa addr argument was not an acceptable address.

The Fn shmdt system call will fail if:

Bq Er EINVAL
The Fa addr argument does not point to a shared memory segment.

SEE ALSO

shmctl(2), shmget(2)