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by Francesco Paolo Lovergine
rules: linking manpages-posix not manpages. |
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.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved |
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by Francesco Paolo Lovergine
* Alligned to linux main manpages edition. |
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.TH "GETC" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" |
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by Francesco Paolo Lovergine
rules: linking manpages-posix not manpages. |
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.\" getc |
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.SH NAME |
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getc \- get a byte from a stream
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.SH SYNOPSIS |
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.LP
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\fB#include <stdio.h>
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.br
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.sp
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int getc(FILE *\fP\fIstream\fP\fB); |
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.br
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\fP
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.SH DESCRIPTION |
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.LP
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The \fIgetc\fP() function shall be equivalent to \fIfgetc\fP() , except |
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that if it is implemented as |
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a macro it may evaluate \fIstream\fP more than once, so the argument |
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should never be an expression with side effects. |
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.SH RETURN VALUE |
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.LP
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Refer to \fIfgetc\fP() . |
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.SH ERRORS |
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.LP
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Refer to \fIfgetc\fP() . |
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.LP
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\fIThe following sections are informative.\fP |
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.SH EXAMPLES |
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.LP
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None. |
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.SH APPLICATION USAGE |
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.LP
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If the integer value returned by \fIgetc\fP() is stored into a variable |
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of type \fBchar\fP and then compared against the |
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integer constant EOF, the comparison may never succeed, because sign-extension |
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of a variable of type \fBchar\fP on widening to |
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integer is implementation-defined. |
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.LP
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Since it may be implemented as a macro, \fIgetc\fP() may treat incorrectly |
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a \fIstream\fP argument with side effects. In |
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particular, \fIgetc\fP(*\fIf\fP++) does not necessarily work as expected. |
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Therefore, use of this function should be preceded by |
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\fB"#undef getc"\fP in such situations; \fIfgetc\fP() could also be |
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used. |
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.SH RATIONALE |
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.LP
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None. |
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.SH FUTURE DIRECTIONS |
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.LP
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None. |
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.SH SEE ALSO |
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.LP
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\fIfgetc\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001, |
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\fI<stdio.h>\fP |
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.SH COPYRIGHT |
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Portions of this text are reprinted and reproduced in electronic form |
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from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology |
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-- Portable Operating System Interface (POSIX), The Open Group Base |
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Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of |
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Electrical and Electronics Engineers, Inc and The Open Group. In the |
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event of any discrepancy between this version and the original IEEE and |
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The Open Group Standard, the original IEEE and The Open Group Standard |
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is the referee document. The original Standard can be obtained online at |
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http://www.opengroup.org/unix/online.html . |