Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/sys/src/cmd/tcl/doc/eof.n

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


'\"
'\" 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: eof.n,v 1.9 2007/12/13 15:22:32 dgp Exp $
'\" 
.so man.macros
.TH eof n 7.5 Tcl "Tcl Built-In Commands"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
eof \- Check for end of file condition on channel
.SH SYNOPSIS
\fBeof \fIchannelId\fR
.BE

.SH DESCRIPTION
.PP
Returns 1 if an end of file condition occurred during the most
recent input operation on \fIchannelId\fR (such as \fBgets\fR),
0 otherwise.
.PP
\fIChannelId\fR must be an identifier for an open channel such as a
Tcl standard channel (\fBstdin\fR, \fBstdout\fR, or \fBstderr\fR),
the return value from an invocation of \fBopen\fR or \fBsocket\fR, or
the result of a channel creation command provided by a Tcl extension.
.SH EXAMPLES
Read and print out the contents of a file line-by-line:
.CS
set f [open somefile.txt]
while {1} {
    set line [gets $f]
    if {[\fBeof\fR $f]} {
        close $f
        break
    }
    puts "Read line: $line"
}
.CE
.PP
Read and print out the contents of a file by fixed-size records:
.CS
set f [open somefile.dat]
fconfigure $f -translation binary
set recordSize 40
while {1} {
    set record [read $f $recordSize]
    if {[\fBeof\fR $f]} {
        close $f
        break
    }
    puts "Read record: $record"
}
.CE

.SH "SEE ALSO"
file(n), open(n), close(n), fblocked(n), Tcl_StandardChannels(3)

.SH KEYWORDS
channel, end of file

Bell Labs OSI certified Powered by Plan 9

(Return to Plan 9 Home Page)

Copyright © 2021 Plan 9 Foundation. All Rights Reserved.
Comments to webmaster@9p.io.