Welcome to section 2
Since there are thousands of different man pages in the database, it is divided into sections that function roughly like groups. A certain type of man page belongs to a section. It's amazing how many manuals there actually are out there. We try to have as many man pages as possible so that people can easily seek help on our site.
There are approximately 9 sections that are used to divide all manuals into different chapters. Some are about commands for Linux while there are sections for devices and libraries. Take a look at the index page to see all sections. You can find it by clicking the home button.
Below you can search all man pages that belongs to the 2 section.
| Name | Description |
| _Exit | Terminate the calling process |
| __clone2 | Create a child process |
| _exit | Terminate the calling process |
| _llseek | Reposition read/write file offset |
| _newselect | Synchronous I/O multiplexing |
| _syscall | Invoking a system call without library support (OBSOLETE) |
| _sysctl | Read/write system parameters |
| aa_change_hat | Change to or from a "hat" within a AppArmor profile |
| aa_change_profile | Change a tasks profile |
| aa_find_mountpoint | Find where the apparmor interface filesystem is mounted |
| aa_getcon | Get task confinement information |
| aa_query_label | Query access permission associated with a label |
| aa_stack_profile | Combine multiple profiles to confine a task |
| accept | Accept a connection on a socket |
| accept4 | Accept a connection on a socket |
| access | Check user's permissions for a file |
| acct | Switch process accounting on or off |
| add_key | Add a key to the kernel's key management facility |
| adjtimex | Tune kernel clock |
| afs_syscall | Unimplemented system calls |
| alarm | Set an alarm clock for delivery of a signal |
| alloc_hugepages | Allocate or free huge pages |
| arch_prctl | Set architecture-specific thread state |
| arm_fadvise | Predeclare an access pattern for file data |
| arm_fadvise64_64 | Predeclare an access pattern for file data |
| arm_sync_file_range | Sync a file segment with disk |
| bdflush | Start, flush, or tune buffer-dirty-flush daemon |
| bind | Bind a name to a socket |
| bpf | Perform a command on an extended BPF map or program |
| break | Unimplemented system calls |
| brk | Change data segment size |
| cacheflush | Flush contents of instruction and/or data cache |
| capget | Set/get capabilities of thread(s) |
| capset | Set/get capabilities of thread(s) |
| chdir | Change working directory |
| chmod | Change permissions of a file |
| chown | Change ownership of a file |
| chown32 | Change ownership of a file |
| chroot | Change root directory |
| clock_adjtime | Tune kernel clock |
| clock_getres | Clock and time functions |
| clock_gettime | Clock and time functions |
| clock_nanosleep | High-resolution sleep with specifiable clock |
| clock_settime | Clock and time functions |
| clone | Create a child process |
| clone2 | Create a child process |
| clone3 | Create a child process |
| close | Close a file descriptor |
| close_range | Close all file descriptors in a given range |
| connect | Initiate a connection on a socket |
| copy_file_range | Copy a range of data from one file to another |
| creat | Open and possibly create a file |
| create_module | Create a loadable module entry |
| delete_module | Unload a kernel module |
| dup | Duplicate a file descriptor |
| dup2 | Duplicate a file descriptor |
| dup3 | Duplicate a file descriptor |
| epoll_create | Open an epoll file descriptor |
| epoll_create1 | Open an epoll file descriptor |
| epoll_ctl | Control interface for an epoll file descriptor |
| epoll_pwait | Wait for an I/O event on an epoll file descriptor |
| epoll_pwait2 | Wait for an I/O event on an epoll file descriptor |
| epoll_wait | Wait for an I/O event on an epoll file descriptor |
| eventfd | Create a file descriptor for event notification |
| eventfd2 | Create a file descriptor for event notification |
| execve | Execute program |
| execveat | Execute program relative to a directory file descriptor |
| exit | Terminate the calling process |
| exit_group | Exit all threads in a process |
| faccessat | Check user's permissions for a file |
| faccessat2 | Check user's permissions for a file |
| fadvise64 | Predeclare an access pattern for file data |
| fadvise64_64 | Predeclare an access pattern for file data |
| fallocate | Manipulate file space |
| fanotify_init | Create and initialize fanotify group |
| fanotify_mark | Add, remove, or modify an fanotify mark on a filesystem object |
| fattach | Unimplemented system calls |
| fchdir | Change working directory |
| fchmod | Change permissions of a file |
| fchmodat | Change permissions of a file |
| fchown | Change ownership of a file |
| fchown32 | Change ownership of a file |
| fchownat | Change ownership of a file |
| fcntl | Manipulate file descriptor |
| fcntl64 | Manipulate file descriptor |
| fdatasync | Synchronize a file's in-core state with storage device |
| fdetach | Unimplemented system calls |
| fgetxattr | Retrieve an extended attribute value |
| finit_module | Load a kernel module |
| flistxattr | List extended attribute names |
| flock | Apply or remove an advisory lock on an open file |
| fork | Create a child process |
| free_hugepages | Allocate or free huge pages |
| fremovexattr | Remove an extended attribute |
| fsetxattr | Set an extended attribute value |
| fstat | Get file status |
| fstat64 | Get file status |
| fstatat | Get file status |
| fstatat64 | Get file status |
| fstatfs | Get filesystem statistics |
| fstatfs64 | Get filesystem statistics |
| fsync | Synchronize a file's in-core state with storage device |
| ftruncate | Truncate a file to a specified length |
| ftruncate64 | Truncate a file to a specified length |
| futex | Fast user-space locking |
| futimesat | Change timestamps of a file relative to a directory file descriptor |
| get_kernel_syms | Retrieve exported kernel and module symbols |
| get_mempolicy | Retrieve NUMA memory policy for a thread |
| get_robust_list | Get/set list of robust futexes |
| get_thread_area | Manipulate thread-local storage information |
| getcpu | Determine CPU and NUMA node on which the calling thread is running |
| getcwd | Get current working directory |
| getdents | Get directory entries |
| getdents64 | Get directory entries |
| getdomainname | Get/set NIS domain name |
| getegid | Get group identity |
| getegid32 | Get group identity |
| geteuid | Get user identity |
| geteuid32 | Get user identity |
| getgid | Get group identity |
| getgid32 | Get group identity |
| getgroups | Get/set list of supplementary group IDs |
| getgroups32 | Get/set list of supplementary group IDs |
| gethostname | Get/set hostname |
| getitimer | Get or set value of an interval timer |
| getmsg | Unimplemented system calls |
| getpagesize | Get memory page size |
| getpeername | Get name of connected peer socket |
| getpgid | Set/get process group |
| getpgrp | Set/get process group |
| getpid | Get process identification |
| getpmsg | Unimplemented system calls |
| getppid | Get process identification |
| getpriority | Get/set program scheduling priority |
| getrandom | Obtain a series of random bytes |
| getresgid | Get real, effective, and saved user/group IDs |
| getresgid32 | Get real, effective, and saved user/group IDs |
| getresuid | Get real, effective, and saved user/group IDs |
| getresuid32 | Get real, effective, and saved user/group IDs |
| getrlimit | Get/set resource limits |
| getrusage | Get resource usage |
| getsid | Get session ID |
| getsockname | Get socket name |
| getsockopt | Get and set options on sockets |
| gettid | Get thread identification |
| gettimeofday | Get / set time |
| getuid | Get user identity |
| getuid32 | Get user identity |
| getunwind | Copy the unwind data to caller's buffer |
| getxattr | Retrieve an extended attribute value |
| gtty | Unimplemented system calls |
| idle | Make process 0 idle |
| inb | Port I/O |
| inb_p | Port I/O |
| init_module | Load a kernel module |
| inl | Port I/O |
| inl_p | Port I/O |
| inotify_add_watch | Add a watch to an initialized inotify instance |
| inotify_init | Initialize an inotify instance |
| inotify_init1 | Initialize an inotify instance |
| inotify_rm_watch | Remove an existing watch from an inotify instance |
| insb | Port I/O |
| insl | Port I/O |
| insw | Port I/O |
| intro | Introduction to system calls |
| inw | Port I/O |
| inw_p | Port I/O |
| io_cancel | Cancel an outstanding asynchronous I/O operation |
| io_destroy | Destroy an asynchronous I/O context |
| io_getevents | Read asynchronous I/O events from the completion queue |
| io_setup | Create an asynchronous I/O context |
| io_submit | Submit asynchronous I/O blocks for processing |
| io_uring_enter | Initiate and/or complete asynchronous I/O |
| io_uring_enter2 | Initiate and/or complete asynchronous I/O |
| io_uring_register | Register files or user buffers for asynchronous I/O |
| io_uring_setup | Setup a context for performing asynchronous I/O |
| ioctl | Control device |
| ioctl_console | Ioctls for console terminal and virtual consoles |
| ioctl_fat | Manipulating the FAT filesystem |
| ioctl_ficlone | Share some the data of one file with another file |
| ioctl_ficlonerange | Share some the data of one file with another file |
| ioctl_fideduperange | Share some the data of one file with another file |
| ioctl_fslabel | Get or set a filesystem label |
| ioctl_getfsmap | Retrieve the physical layout of the filesystem |
| ioctl_iflags | Ioctl() operations for inode flags |
| ioctl_ns | Ioctl() operations for Linux namespaces |
| ioctl_pipe | Ioctl() operations for General notification mechanism |
| ioctl_tty | Ioctls for terminals and serial lines |
| ioctl_userfaultfd | Create a file descriptor for handling page faults in user space |
| ioctl_xfs_ag_geometry | Query XFS allocation group geometry information |
| ioctl_xfs_bulkstat | Query information for a batch of XFS inodes |
| ioctl_xfs_fsbulkstat | Query information for a batch of XFS inodes |
| ioctl_xfs_fscounts | Query XFS summary counter information |
| ioctl_xfs_fsgeometry | Report XFS filesystem layout and features |
| ioctl_xfs_fsgetxattr | Query information for an open file |
| ioctl_xfs_fsinumbers | Extract a list of valid inode numbers from an XFS filesystem |
| ioctl_xfs_getbmapx | Query extent information for an open file |
| ioctl_xfs_getresblks | Query and set XFS free space reservation information |
| ioctl_xfs_goingdown | Shut down an XFS filesystem |
| ioctl_xfs_inumbers | Query allocation information for groups of XFS inodes |
| ioctl_xfs_scrub_metadata | Check XFS filesystem metadata |
| ioperm | Set port input/output permissions |
| iopl | Change I/O privilege level |
| ioprio_get | Get/set I/O scheduling class and priority |
| ioprio_set | Get/set I/O scheduling class and priority |
| ipc | System V IPC system calls |
| isastream | Unimplemented system calls |
| kcmp | Compare two processes to determine if they share a kernel resource |
| kexec_file_load | Load a new kernel for later execution |
| kexec_load | Load a new kernel for later execution |
| keyctl | Manipulate the kernel's key management facility |
| kill | Send signal to a process |
| landlock_add_rule | Add a new Landlock rule to a ruleset |
| landlock_create_ruleset | Create a new Landlock ruleset |
| landlock_restrict_self | Enforce a Landlock ruleset |
| lchown | Change ownership of a file |
| lchown32 | Change ownership of a file |
| lgetxattr | Retrieve an extended attribute value |
| link | Make a new name for a file |
| linkat | Make a new name for a file |
| listen | Listen for connections on a socket |
| listxattr | List extended attribute names |
| llistxattr | List extended attribute names |
| llseek | Reposition read/write file offset |
| lock | Unimplemented system calls |
| lookup_dcookie | Return a directory entry's path |
| lremovexattr | Remove an extended attribute |
| lseek | Reposition read/write file offset |
| lsetxattr | Set an extended attribute value |
| lstat | Get file status |
| lstat64 | Get file status |
| madvise | Give advice about use of memory |
| madvise1 | Unimplemented system calls |
| mbind | Set memory policy for a memory range |
| membarrier | Issue memory barriers on a set of threads |
| memfd_create | Create an anonymous file |
| memfd_secret | Create an anonymous RAM-based file to access secret memory regions |
| migrate_pages | Move all pages in a process to another set of nodes |
| mincore | Determine whether pages are resident in memory |
| mkdir | Create a directory |
| mkdirat | Create a directory |
| mknod | Create a special or ordinary file |
| mknodat | Create a special or ordinary file |
| mlock | Lock and unlock memory |
| mlock2 | Lock and unlock memory |
| mlockall | Lock and unlock memory |
| mmap | Map or unmap files or devices into memory |
| mmap2 | Map files or devices into memory |
| modify_ldt | Get or set a per-process LDT entry |
| mount | Mount filesystem |
| mount_setattr | Change properties of a mount or mount tree |
| move_pages | Move individual pages of a process to another node |
| mprotect | Set protection on a region of memory |
| mpx | Unimplemented system calls |
| mq_getsetattr | Get/set message queue attributes |
| mq_notify | Register for notification when a message is available |
| mq_open | Open a message queue |
| mq_timedreceive | Receive a message from a message queue |
| mq_timedsend | Send a message to a message queue |
| mq_unlink | Remove a message queue |
| mremap | Remap a virtual memory address |
| msgctl | System V message control operations |
| msgget | Get a System V message queue identifier |
| msgop | System V message queue operations |
| msgrcv | System V message queue operations |
| msgsnd | System V message queue operations |
| msync | Synchronize a file with a memory map |
| munlock | Lock and unlock memory |
| munlockall | Lock and unlock memory |
| munmap | Map or unmap files or devices into memory |
| name_to_handle_at | Obtain handle for a pathname and open file via a handle |
| nanosleep | High-resolution sleep |
| newfstatat | Get file status |
| nfsservctl | Syscall interface to kernel nfs daemon |
| nice | Change process priority |
| oldfstat | Get file status |
| oldlstat | Get file status |
| oldolduname | Get name and information about current kernel |
| oldstat | Get file status |
| olduname | Get name and information about current kernel |
| open | Open and possibly create a file |
| open_by_handle_at | Obtain handle for a pathname and open file via a handle |
| openat | Open and possibly create a file |
| openat2 | Open and possibly create a file (extended) |
| outb | Port I/O |
| outb_p | Port I/O |
| outl | Port I/O |
| outl_p | Port I/O |
| outsb | Port I/O |
| outsl | Port I/O |
| outsw | Port I/O |
| outw | Port I/O |
| outw_p | Port I/O |
| pause | Wait for signal |
| pciconfig_iobase | Pci device information handling |
| pciconfig_read | Pci device information handling |
| pciconfig_write | Pci device information handling |
| perf_event_open | Set up performance monitoring |
| perfmonctl | Interface to IA-64 performance monitoring unit |
| personality | Set the process execution domain |
| phys | Unimplemented system calls |
| pidfd_getfd | Obtain a duplicate of another process's file descriptor |
| pidfd_open | Obtain a file descriptor that refers to a process |
| pidfd_send_signal | Send a signal to a process specified by a file descriptor |
| pipe | Create pipe |
| pipe2 | Create pipe |
| pivot_root | Change the root mount |
| pkey_alloc | Allocate or free a protection key |
| pkey_free | Allocate or free a protection key |
| pkey_mprotect | Set protection on a region of memory |
| poll | Wait for some event on a file descriptor |
| posix_fadvise | Predeclare an access pattern for file data |
| ppoll | Wait for some event on a file descriptor |
| prctl | Operations on a process or thread |
| pread | Read from or write to a file descriptor at a given offset |
| pread64 | Read from or write to a file descriptor at a given offset |
| preadv | Read or write data into multiple buffers |
| preadv2 | Read or write data into multiple buffers |
| prlimit | Get/set resource limits |
| prlimit64 | Get/set resource limits |
| process_madvise | Give advice about use of memory to a process |
| process_vm_readv | Transfer data between process address spaces |
| process_vm_writev | Transfer data between process address spaces |
| prof | Unimplemented system calls |
| pselect | Synchronous I/O multiplexing |
| pselect6 | Synchronous I/O multiplexing |
| ptrace | Process trace |
| putmsg | Unimplemented system calls |
| putpmsg | Unimplemented system calls |
| pwrite | Read from or write to a file descriptor at a given offset |
| pwrite64 | Read from or write to a file descriptor at a given offset |
| pwritev | Read or write data into multiple buffers |
| pwritev2 | Read or write data into multiple buffers |
| query_module | Query the kernel for various bits pertaining to modules |
| quotactl | Manipulate disk quotas |
| read | Read from a file descriptor |
| readahead | Initiate file readahead into page cache |
| readdir | Read directory entry |
| readlink | Read value of a symbolic link |
| readlinkat | Read value of a symbolic link |
| readv | Read or write data into multiple buffers |
| reboot | Reboot or enable/disable Ctrl-Alt-Del |
| recv | Receive a message from a socket |
| recvfrom | Receive a message from a socket |
| recvmmsg | Receive multiple messages on a socket |
| recvmsg | Receive a message from a socket |
| remap_file_pages | Create a nonlinear file mapping |
| removexattr | Remove an extended attribute |
| rename | Change the name or location of a file |
| renameat | Change the name or location of a file |
| renameat2 | Change the name or location of a file |
| request_key | Request a key from the kernel's key management facility |
| restart_syscall | Restart a system call after interruption by a stop signal |
| rmdir | Delete a directory |
| rt_sigaction | Examine and change a signal action |
| rt_sigpending | Examine pending signals |
| rt_sigprocmask | Examine and change blocked signals |
| rt_sigqueueinfo | Queue a signal and data |
| rt_sigreturn | Return from signal handler and cleanup stack frame |
| rt_sigsuspend | Wait for a signal |
| rt_sigtimedwait | Synchronously wait for queued signals |
| rt_tgsigqueueinfo | Queue a signal and data |
| s390_guarded_storage | Operations with z/Architecture guarded storage facility |
| s390_pci_mmio_read | Transfer data to/from PCI MMIO memory page |
| s390_pci_mmio_write | Transfer data to/from PCI MMIO memory page |
| s390_runtime_instr | Enable/disable s390 CPU run-time instrumentation |
| s390_sthyi | Emulate STHYI instruction |
| sbrk | Change data segment size |
| sched_get_priority_max | Get static priority range |
| sched_get_priority_min | Get static priority range |
| sched_getaffinity | Set and get a thread's CPU affinity mask |
| sched_getattr | Set and get scheduling policy and attributes |
| sched_getparam | Set and get scheduling parameters |
| sched_getscheduler | Set and get scheduling policy/parameters |
| sched_rr_get_interval | Get the SCHED_RR interval for the named process |
| sched_setaffinity | Set and get a thread's CPU affinity mask |
| sched_setattr | Set and get scheduling policy and attributes |
| sched_setparam | Set and get scheduling parameters |
| sched_setscheduler | Set and get scheduling policy/parameters |
| sched_yield | Yield the processor |
| seccomp | Operate on Secure Computing state of the process |
| seccomp_unotify | Seccomp user-space notification mechanism |
| security | Unimplemented system calls |
| select | Synchronous I/O multiplexing |
| select_tut | Synchronous I/O multiplexing |
| semctl | System V semaphore control operations |
| semget | Get a System V semaphore set identifier |
| semop | System V semaphore operations |
| semtimedop | System V semaphore operations |
| send | Send a message on a socket |
| sendfile | Transfer data between file descriptors |
| sendfile64 | Transfer data between file descriptors |
| sendmmsg | Send multiple messages on a socket |
| sendmsg | Send a message on a socket |
| sendto | Send a message on a socket |
| set_mempolicy | Set default NUMA memory policy for a thread and its children |
| set_robust_list | Get/set list of robust futexes |
| set_thread_area | Manipulate thread-local storage information |
| set_tid_address | Set pointer to thread ID |
| setdomainname | Get/set NIS domain name |
| setegid | Set effective user or group ID |
| seteuid | Set effective user or group ID |
| setfsgid | Set group identity used for filesystem checks |
| setfsgid32 | Set group identity used for filesystem checks |
| setfsuid | Set user identity used for filesystem checks |
| setfsuid32 | Set user identity used for filesystem checks |
| setgid | Set group identity |
| setgid32 | Set group identity |
| setgroups | Get/set list of supplementary group IDs |
| setgroups32 | Get/set list of supplementary group IDs |
| sethostname | Get/set hostname |
| setitimer | Get or set value of an interval timer |
| setns | Reassociate thread with a namespace |
| setpgid | Set/get process group |
| setpgrp | Set/get process group |
| setpriority | Get/set program scheduling priority |
| setregid | Set real and/or effective user or group ID |
| setregid32 | Set real and/or effective user or group ID |
| setresgid | Set real, effective, and saved user or group ID |
| setresgid32 | Set real, effective, and saved user or group ID |
| setresuid | Set real, effective, and saved user or group ID |
| setresuid32 | Set real, effective, and saved user or group ID |
| setreuid | Set real and/or effective user or group ID |
| setreuid32 | Set real and/or effective user or group ID |
| setrlimit | Get/set resource limits |
| setsid | Creates a session and sets the process group ID |
| setsockopt | Get and set options on sockets |
| settimeofday | Get / set time |
| setuid | Set user identity |
| setuid32 | Set user identity |
| setup | Setup devices and filesystems, mount root filesystem |
| setxattr | Set an extended attribute value |
| sgetmask | Manipulation of signal mask (obsolete) |
| shmat | System V shared memory operations |
| shmctl | System V shared memory control |
| shmdt | System V shared memory operations |
| shmget | Allocates a System V shared memory segment |
| shmop | System V shared memory operations |
| shutdown | Shut down part of a full-duplex connection |
| sigaction | Examine and change a signal action |
| sigaltstack | Set and/or get signal stack context |
| signal | ANSI C signal handling |
| signalfd | Create a file descriptor for accepting signals |
| signalfd4 | Create a file descriptor for accepting signals |
| sigpending | Examine pending signals |
| sigprocmask | Examine and change blocked signals |
| sigreturn | Return from signal handler and cleanup stack frame |
| sigsuspend | Wait for a signal |
| sigtimedwait | Synchronously wait for queued signals |
| sigwaitinfo | Synchronously wait for queued signals |
| socket | Create an endpoint for communication |
| socketcall | Socket system calls |
| socketpair | Create a pair of connected sockets |
| splice | Splice data to/from a pipe |
| spu_create | Create a new spu context |
| spu_run | Execute an SPU context |
| ssetmask | Manipulation of signal mask (obsolete) |
| stat | Get file status |
| stat64 | Get file status |
| statfs | Get filesystem statistics |
| statfs64 | Get filesystem statistics |
| statx | Get file status (extended) |
| stime | Set time |
| stty | Unimplemented system calls |
| subpage_prot | Define a subpage protection for an address range |
| swapoff | Start/stop swapping to file/device |
| swapon | Start/stop swapping to file/device |
| symlink | Make a new name for a file |
| symlinkat | Make a new name for a file |
| sync | Commit filesystem caches to disk |
| sync_file_range | Sync a file segment with disk |
| sync_file_range2 | Sync a file segment with disk |
| syncfs | Commit filesystem caches to disk |
| syscall | Indirect system call |
| syscalls | Linux system calls |
| sysctl | Read/write system parameters |
| sysfs | Get filesystem type information |
| sysinfo | Return system information |
| syslog | Read and/or clear kernel message ring buffer; set console_loglevel |
| tee | Duplicating pipe content |
| tgkill | Send a signal to a thread |
| time | Get time in seconds |
| timer_create | Create a POSIX per-process timer |
| timer_delete | Delete a POSIX per-process timer |
| timer_getoverrun | Get overrun count for a POSIX per-process timer |
| timer_gettime | Arm/disarm and fetch state of POSIX per-process timer |
| timer_settime | Arm/disarm and fetch state of POSIX per-process timer |
| timerfd_create | Timers that notify via file descriptors |
| timerfd_gettime | Timers that notify via file descriptors |
| timerfd_settime | Timers that notify via file descriptors |
| times | Get process times |
| tkill | Send a signal to a thread |
| truncate | Truncate a file to a specified length |
| truncate64 | Truncate a file to a specified length |
| tuxcall | Unimplemented system calls |
| ugetrlimit | Get/set resource limits |
| umask | Set file mode creation mask |
| umount | Unmount filesystem |
| umount2 | Unmount filesystem |
| uname | Get name and information about current kernel |
| unimplemented | Unimplemented system calls |
| unlink | Delete a name and possibly the file it refers to |
| unlinkat | Delete a name and possibly the file it refers to |
| unshare | Disassociate parts of the process execution context |
| uselib | Load shared library |
| userfaultfd | Create a file descriptor for handling page faults in user space |
| ustat | Get filesystem statistics |
| utime | Change file last access and modification times |
| utimensat | Change file timestamps with nanosecond precision |
| utimes | Change file last access and modification times |
| vfork | Create a child process and block parent |
| vhangup | Virtually hangup the current terminal |
| vm86 | Enter virtual 8086 mode |
| vm86old | Enter virtual 8086 mode |
| vmsplice | Splice user pages to/from a pipe |
| vserver | Unimplemented system calls |
| wait | Wait for process to change state |
| wait3 | Wait for process to change state, BSD style |
| wait4 | Wait for process to change state, BSD style |
| waitid | Wait for process to change state |
| waitpid | Wait for process to change state |
| write | Write to a file descriptor |
| writev | Read or write data into multiple buffers |