NAME

fork − create a copy of this process

SYNOPSIS

integer function fork()

DESCRIPTION

Fork creates a copy of the calling process.  The only distinction between the 2 processes is that the value returned to one of them (referred to as the ‘parent’ process) will be the process id of the copy.  The copy is usually referred to as the ‘child’ process.  The value returned to the ‘child’ process will be zero. 

All logical units open for writing are flushed before the fork to avoid duplication of the contents of I/O buffers in the external file(s). 

If the returned value is negative, it indicates an error and will be the negation of the system error code.  See perror(3F). 

A corresponding exec routine has not been provided because there is no satisfactory way to retain open logical units across the exec.  However, the usual function of fork/exec can be performed using system(3F).

FILES

/usr/lib/libU77.a

SEE ALSO

fork(2), wait(3F), kill(3F), system(3F), perror(3F)

4.2 Berkeley Distribution  —  Revision 1.2 of 19/10/88