c语⾔sighold函数,POSIX头⽂件和函数速查POSIX包含多个标准如C接⼝，命令⾏，shell等等
对于C的API
_POSIX_C_SOURCE 检测宏定义
ANIS C 只定义了EDOM、EILSEQ、ERANGE[E2BIG]Argument list too long.
[EACCES]Permission denied.
[EADDRINUSE]Address in use.
[EADDRNOTAVAIL]Address not available.
[EAFNOSUPPORT]Address family not supported.
[EAGAIN]Resource unavailable, try again (may be the same value as [EWOULDBLOCK]).
[EALREADY]Connection already in progress.
[EBADF]Bad file descriptor.
[EBADMSG]Bad message.
[EBUSY]Device or resource busy.
[ECANCELED]Operation canceled.
[ECHILD]No child processes.
[ECONNABORTED]Connection aborted.
[ECONNREFUSED]Connection refused.
[ECONNRESET]Connection reset.
[EDEADLK]Resource deadlock would occur.
[EDESTADDRREQ]Destination address required.
[EDOM]Mathematics argument out of domain of function.
[EDQUOT]Reserved.
[EEXIST]File exists.
[EFAULT]Bad address.
[EFBIG]File too large.
[EHOSTUNREACH]Host is unreachable.
[EIDRM]Identifier removed.
[EILSEQ]Illegal byte sequence.
[EINPROGRESS]Operation in progress.
[EINTR]Interrupted function.
[EINVAL]Invalid argument.
[EIO]I/O error.
[EISCONN]Socket is connected.
[EISDIR]Is a directory.
[ELOOP]Too many levels of symbolic links.
[EMFILE]File descriptor value too large.
[EMLINK]Too many links.
[EMSGSIZE]Message too large.
[EMULTIHOP]Reserved.
[ENAMETOOLONG]Filename too long.
[ENETDOWN]Network is down.
[ENETRESET]Connection aborted by network.
[ENETUNREACH]Network unreachable.
[ENFILE]Too many files open in system.
[ENOBUFS]No buffer space available.
[ENODATA][OB XSR] No message is available on the STREAM head read queue. [ENODEV]No such device.
[ENOENT]No such file or directory.
[ENOEXEC]Executable file format error.
[ENOLCK]No locks available.
[ENOLINK]Reserved.
[ENOMEM]Not enough space.
[ENOMSG]No message of the desired type.
[ENOPROTOOPT]Protocol not available.
[ENOSPC]No space left on device.
[ENOSR][OB XSR] No STREAM resources.
[ENOSTR][OB XSR] Not a STREAM.
[ENOSYS]Functionality not supported.
[ENOTCONN]The socket is not connected.
[ENOTDIR]Not a directory or a symbolic link to a directory.
[ENOTEMPTY]Directory not empty.
[ENOTRECOVERABLE]State not recoverable.
[ENOTSOCK]Not a socket.
[ENOTSUP]Not supported (may be the same value as [EOPNOTSUPP]).
[ENOTTY]Inappropriate I/O control operation.
[ENXIO]No such device or address.
[EOPNOTSUPP]Operation not supported on socket (may be the same value as [ENOTSUP]).
[EOVERFLOW]Value too large to be stored in data type.
[EOWNERDEAD]Previous owner died.c语言struct头文件
[EPERM]Operation not permitted.
[EPIPE]Broken pipe.
[EPROTO]Protocol error.
[EPROTONOSUPPORT]Protocol not supported.
[EPROTOTYPE]Protocol wrong type for socket.
[ERANGE]Result too large.
[EROFS]Read-only file system.
[ESPIPE]Invalid seek.
[ESRCH]No such process.
[ESTALE]Reserved.
[ETIME][OB XSR] Stream ioctl() timeout.
[ETIMEDOUT]Connection timed out.
[ETXTBSY]Text file busy.
[EWOULDBLOCK]Operation would block (may be the same value as [EAGAIN]). [EXDEV]Cross-device link.
F_DUPFD
F_DUPFD_CLOEXEC
F_GETFD
F_SETFD
F_GETFL
F_SETFL
F_GETLK
F_SETLK
F_SETLKW
F_GETOWN
F_SETOWN
F_RDLCK
F_UNLCK
F_WRLCK
FD_CLOEXEC
O_CLOEXEC
O_CREAT
O_DIRECTORY
O_EXCL
O_NOCTTY
O_NOFOLLOW
O_TRUNC
O_TTY_INIT
O_APPEND
O_DSYNC
O_NONBLOCK
O_RSYNC
O_SYNC
O_ACCMODE
O_EXEC
O_RDONLY
O_RDWR
O_SEARCH
O_WRONLY
AT_FDCWD
AT_EACCESS
AT_SYMLINK_NOFOLLOW
AT_SYMLINK_FOLLOW
AT_REMOVEDIR
POSIX_FADV_DONTNEED
POSIX_FADV_NOREUSE
POSIX_FADV_NORMAL
POSIX_FADV_RANDOM
POSIX_FADV_SEQUENTIAL
POSIX_FADV_WILLNEED
int creat(const char *, mode_t);
int fcntl(int, int, ...);
int open(const char *, int, ...);
int openat(int, const char *, int, ...);
int posix_fadvise(int, off_t, off_t, int); int posix_fallocate(int, off_t, off_t);
int faccessat(int fd, const char *path, int amode, int flag);
int fchmodat(int fd, const char *path, mode_t mode, int flag); int fchownat(int fd, const char *path, uid_t owner, gid_t group,
int flag);
int linkat(int fd1, const char *path1, int fd2,
const char *path2, int flag);
int unlinkat(int fd, const char *path, int flag);
POLLIN
POLLRDNORM
POLLRDBAND
POLLPRI
POLLOUT
POLLWRNORM
POLLWRBAND
POLLERR
POLLHUP
POLLNVAL
int poll(struct pollfd [], nfds_t, int);
SIG_DFL    Request for default signal handling.
SIG_ERR    Return value from signal() in case of error.
SIG_HOLD[OB XSI]    Request that signal be held.
SIG_IGN    Request that signal be ignored.
SIGABRT
SIGALRM
SIGBUS
SIGCHLD
SIGCONT
SIGFPE
SIGHUP
SIGILL
SIGINT
SIGKILL
SIGPIPE