vfork - generate new process in virtual memory

Syntax	#include <unistd.h> pid_t vfork (void);
Description	vfork() is mapped to fork(). See the relevant section for a description.
Return val.	0 or PID	if successful. 0 is returned to the child process, and the process ID of the child process is returned to the parent process.
	-1	to the parent process if an error occurs. No child process is generated. errno is set to indicate the error.
Errors	vfork() will fail if
	EAGAIN	The system-dependent limit to the maximum number of processes possible throughout the system or per user was exceeded. These limits are defined when the system is generated.
	ENOMEM	The swap area is not large enough for the new process.
See also	exec(), exit(), fork(), wait(), unistd.h.