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'\"
'\" 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.
'\" 
.TH eof n 7.5 Tcl "Tcl Built-In Commands"
.so man.macros
.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
.PP
Read and print out the contents of a file line-by-line:
.PP
.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:
.PP
.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