'\"
'\" Copyright (c) 1993 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" RCS: @(#) $Id: gets.n,v 1.2 2003/11/24 05:09:59 bbbush Exp $
'\" 
'\" The definitions below are for supplemental macros used in Tcl/Tk
'\" manual entries.
'\"
'\" .AP type name in/out ?indent?
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'\"	type is type of argument (int, etc.), in/out is either "in", "out",
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'\" .OP cmdName dbName dbClass
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'\"
'\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
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See the \\fBoptions\\fR manual entry for details on the standard options.
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Command-Line Name:	\\fB\\$1\\fR
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\\$1\l'|0\(ul'\\$2
..
.TH gets 3tcl 7.5 Tcl "Tcl Built-In Commands"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
gets \- 從一個通道讀一行
.SH "總覽 SYNOPSIS"
\fBgets \fIchannelId\fR ?\fIvarName\fR?
.BE

.SH "描述 DESCRIPTION"
.PP
這個命令從 \fIchannelId \fR讀下一行，返回直到(但不包括)行結束字符的行中所有字符，並拋棄行結束字符。如果省略了 \fIvarName\fR，把這一行作爲命令的結果返回。如果指定了 \fIvarName\fR ，則把這一行放置到叫這個名字的變量中而返回值是返回的字符總數。
.PP
如果在檢索行結束的時候遇到了文件結束，命令返回直到文件結束可獲得的所有輸入。如果 \fIchannelId\fR在非阻塞模式下並且不能獲得完整的一行的輸入，命令返回一個空串並不消耗任何輸入。因爲文件結束或因爲在非阻塞模式下數據不充足，如果指定了 \fIvarName\fR 並切返回了一個空串，則返回的總數是 -1。注意如果未指定 \fIvarName\fR  則在文件結束和沒有可獲得的完整的一行的情況下產生的結果與輸入行只由一個行結束字符組成同樣。使用\fBeof\fR 和 \fBfblocked\fR命令來區別這三種情況。  

.SH "參見 SEE ALSO"
file(n), eof(n), fblocked(n)

.SH "關鍵字 KEYWORDS"
blocking, channel, end of file, end of line, line, nonblocking, read

.SH "[中文版維護人]"
.B 寒蟬退士
.SH "[中文版最新更新]"
.B 2001/09/02  
.SH "《中國 Linux 論壇 man 手冊頁翻譯計劃》:"
.BI http://cmpp.linuxforum.net
.SH "跋"
.br
本頁面中文版由中文 man 手冊頁計劃提供。
.br
中文 man 手冊頁計劃：\fBhttps://github.com/man-pages-zh/manpages-zh\fR