44 lines
1.2 KiB
Groff
44 lines
1.2 KiB
Groff
.TH SELECT 2 "Jun 9, 2005"
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.UC 4
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.SH NAME
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select, FD_CLR, FD_ISSET, FD_SET, FD_ZERO \- synchronous I/O multiplexing
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.SH SYNOPSIS
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.nf
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.ft B
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#include <sys/select.h>
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int select(int \fInfds\fP, fd_set *\fIreadfds\fP, fd_set *\fIwritefds\fP, fd_set *\fIerrorfds\fP, struct timeval *\fItimeout\fP)
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void FD_CLR(int \fIfd\fP, fd_set *\fIfdset\fP)
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int FD_ISSET(int \fIfd\fP, fd_set *\fIfdset\fP)
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void FD_SET(int \fIfd\fP, fd_set *\fIfdset\fP)
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void FD_ZERO(fd_set *\fIfdset\fP)
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.ft R
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.fi
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.SH DESCRIPTION
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.B Select
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examines the file descriptors given in the sets
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.IR readfds ,
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.IR writefds ,
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and
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.IR errorfds ,
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up to and including file descriptor
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.IR nfds -1
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, for reading, writing, or exceptional conditions, respectively.
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.B Select
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currently supports regular files, pipes, named pipes,
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inet, and tty file descriptors (including pty).
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If the
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.I readfds
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argument is not a null pointer, it points to an object of type fd_set
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that on input specifies the file descriptors to be checked for being
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ready to read, and on output indicates which file descriptors are ready
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to read.
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.I Writefds
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and
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.I errorfds
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have an analogous meaning for file descriptors to be checked for being
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ready to read, respectively have pending exceptional (error) conditions.
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