semctl - SysV semaphore control operations

- NAME
- SYNOPSIS
- DESCRIPTION

# NAME

semctl - SysV semaphore control operations

# SYNOPSIS

semctl ID,SEMNUM,CMD,ARG

# DESCRIPTION

Calls the System V IPC function `semctl`. You'll probably have to say

        use IPC::SysV;

first to get the correct constant definitions. If CMD is IPC_STAT or GETALL, then ARG must be a variable that will hold the returned semid_ds structure or semaphore value array. Returns like `ioctl`: the undefined value for error, ```0 but true`'' for zero, or the actual return value otherwise. The ARG must consist of a vector of native short integers, which may be created with `pack("s!",(0)x$nsem)`. See also SysV IPC in the perlipc manpage, `IPC::SysV`, `IPC::Semaphore` documentation.

semctl - SysV semaphore control operations