#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * The NtCreateMutant routine creates a mutant object, sets the initial state of the mutant to the specified value,
 * and opens a handle to the object with the specified desired access.
 *
 * \param MutantHandle A pointer to a variable that receives the mutant object handle.
 * \param DesiredAccess The access mask that specifies the requested access to the mutant object.
 * \param ObjectAttributes A pointer to an OBJECT_ATTRIBUTES structure that specifies the object attributes.
 * \param InitialOwner If TRUE, the calling thread is the initial owner of the mutant object.
 * \return NTSTATUS Successful or errant status.
 * \remarks A mutant is an ownership-tracked, recursively acquirable mutex. NULL ObjectAttributes
 * creates an unnamed object. InitialOwner applies only to a newly created mutant. With
 * OBJ_OPENIF, an existing named mutant is returned with STATUS_OBJECT_NAME_EXISTS; TRUE
 * InitialOwner does not acquire it. Acquire an existing mutant by waiting instead.
 * Release each acquired recursion level with NtReleaseMutant; NtClose closes the handle
 * but is not a substitute for releasing ownership.
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateMutant(
    _Out_ PHANDLE MutantHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_ BOOLEAN InitialOwner
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateMutant(
    _Out_ PHANDLE MutantHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_ BOOLEAN InitialOwner
    );

#endif
View code on GitHub