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diff --git a/man-pages-posix-2013/man3p/fgetc.3p b/man-pages-posix-2013/man3p/fgetc.3p new file mode 100644 index 0000000..fbc8008 --- /dev/null +++ b/man-pages-posix-2013/man3p/fgetc.3p @@ -0,0 +1,175 @@ +'\" et +.TH FGETC "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +fgetc +\(em get a byte from a stream +.SH SYNOPSIS +.LP +.nf +#include <stdio.h> +.P +int fgetc(FILE *\fIstream\fP); +.fi +.SH DESCRIPTION +The functionality described on this reference page is aligned with the +ISO\ C standard. Any conflict between the requirements described here and the +ISO\ C standard is unintentional. This volume of POSIX.1\(hy2008 defers to the ISO\ C standard. +.P +If the end-of-file indicator for the input stream pointed to by +.IR stream +is not set and a next byte is present, the +\fIfgetc\fR() +function shall obtain the next byte as an +.BR "unsigned char" +converted to an +.BR int , +from the input stream pointed to by +.IR stream , +and advance the associated file position indicator for the stream (if +defined). Since +\fIfgetc\fR() +operates on bytes, reading a character consisting of multiple bytes (or +``a multi-byte character'') may require multiple calls to +\fIfgetc\fR(). +.P +The +\fIfgetc\fR() +function may mark the last data access timestamp of the file +associated with +.IR stream +for update. The last data access timestamp shall be marked for +update by the first successful execution of +\fIfgetc\fR(), +\fIfgets\fR(), +\fIfread\fR(), +\fIfscanf\fR(), +\fIgetc\fR(), +\fIgetchar\fR(), +\fIgetdelim\fR(), +\fIgetline\fR(), +\fIgets\fR(), +or +\fIscanf\fR() +using +.IR stream +that returns data not supplied by a prior call to +\fIungetc\fR(). +.SH "RETURN VALUE" +Upon successful completion, +\fIfgetc\fR() +shall return the next byte from the input stream pointed to by +.IR stream . +If the end-of-file indicator for the stream is set, or if the +stream is at end-of-file, the end-of-file indicator for the +stream shall be set and +\fIfgetc\fR() +shall return EOF. If a read error occurs, the error indicator for the +stream shall be set, +\fIfgetc\fR() +shall return EOF, +and shall set +.IR errno +to indicate the error. +.SH ERRORS +The +\fIfgetc\fR() +function shall fail if data needs to be read and: +.TP +.BR EAGAIN +The O_NONBLOCK flag is set for the file descriptor underlying +.IR stream +and the thread would be delayed in the +\fIfgetc\fR() +operation. +.TP +.BR EBADF +The file descriptor underlying +.IR stream +is not a valid file descriptor open for reading. +.TP +.BR EINTR +The read operation was terminated due to the receipt of a signal, and +no data was transferred. +.TP +.BR EIO +A physical I/O error has occurred, or the process is in a background +process group attempting to read from its controlling terminal, and +either the calling thread is blocking SIGTTIN or the process is ignoring +SIGTTIN or the process group of the process is orphaned. +This error may also be generated for implementation-defined reasons. +.TP +.BR EOVERFLOW +The file is a regular file and an attempt was made to read at or beyond +the offset maximum associated with the corresponding stream. +.P +The +\fIfgetc\fR() +function may fail if: +.TP +.BR ENOMEM +Insufficient storage space is available. +.TP +.BR ENXIO +A request was made of a nonexistent device, or the request was outside +the capabilities of the device. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +If the integer value returned by +\fIfgetc\fR() +is stored into a variable of type +.BR char +and then compared against the integer constant EOF, the comparison may +never succeed, because sign-extension of a variable of type +.BR char +on widening to integer is implementation-defined. +.P +The +\fIferror\fR() +or +\fIfeof\fR() +functions must be used to distinguish between an error condition and an +end-of-file condition. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "Section 2.5" ", " "Standard I/O Streams", +.IR "\fIfeof\fR\^(\|)", +.IR "\fIferror\fR\^(\|)", +.IR "\fIfgets\fR\^(\|)", +.IR "\fIfread\fR\^(\|)", +.IR "\fIfscanf\fR\^(\|)", +.IR "\fIgetchar\fR\^(\|)", +.IR "\fIgetc\fR\^(\|)", +.IR "\fIgets\fR\^(\|)", +.IR "\fIungetc\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<stdio.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |