diff options
Diffstat (limited to '')
| -rw-r--r-- | man3/fgetc.3 | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/man3/fgetc.3 b/man3/fgetc.3 new file mode 100644 index 0000000..1b13d61 --- /dev/null +++ b/man3/fgetc.3 @@ -0,0 +1,153 @@ +'\" t +.\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de) +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" Modified Wed Jul 28 11:12:07 1993 by Rik Faith (faith@cs.unc.edu) +.\" Modified Fri Sep 8 15:48:13 1995 by Andries Brouwer (aeb@cwi.nl) +.TH fgetc 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +fgetc, fgets, getc, getchar, ungetc \- input of characters and strings +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <stdio.h> +.PP +.BI "int fgetc(FILE *" stream ); +.BI "int getc(FILE *" stream ); +.B "int getchar(void);" +.PP +.BI "char *fgets(char " s "[restrict ." size "], int " size ", \ +FILE *restrict " stream ); +.PP +.BI "int ungetc(int " c ", FILE *" stream ); +.fi +.SH DESCRIPTION +.BR fgetc () +reads the next character from +.I stream +and returns it as an +.I unsigned char +cast to an +.IR int , +or +.B EOF +on end of file or error. +.PP +.BR getc () +is equivalent to +.BR fgetc () +except that it may be implemented as a macro which evaluates +.I stream +more than once. +.PP +.BR getchar () +is equivalent to +.BI "getc(" stdin ) \fR. +.PP +.BR fgets () +reads in at most one less than +.I size +characters from +.I stream +and stores them into the buffer pointed to by +.IR s . +Reading stops after an +.B EOF +or a newline. +If a newline is read, it is stored into the buffer. +A terminating null byte (\[aq]\e0\[aq]) +is stored after the last character in the buffer. +.PP +.BR ungetc () +pushes +.I c +back to +.IR stream , +cast to +.IR "unsigned char" , +where it is available for subsequent read operations. +Pushed-back characters +will be returned in reverse order; only one pushback is guaranteed. +.PP +Calls to the functions described here can be mixed with each other and with +calls to other input functions from the +.I stdio +library for the same input stream. +.PP +For nonlocking counterparts, see +.BR unlocked_stdio (3). +.SH RETURN VALUE +.BR fgetc (), +.BR getc (), +and +.BR getchar () +return the character read as an +.I unsigned char +cast to an +.I int +or +.B EOF +on end of file or error. +.PP +.BR fgets () +returns +.I s +on success, and NULL +on error or when end of file occurs while no characters have been read. +.PP +.BR ungetc () +returns +.I c +on success, or +.B EOF +on error. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR fgetc (), +.BR fgets (), +.BR getc (), +.BR getchar (), +.BR ungetc () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +POSIX.1-2001, C89. +.SH NOTES +It is not advisable to mix calls to input functions from the +.I stdio +library with low-level calls to +.BR read (2) +for the file descriptor associated with the input stream; the results +will be undefined and very probably not what you want. +.SH SEE ALSO +.BR read (2), +.BR write (2), +.BR ferror (3), +.BR fgetwc (3), +.BR fgetws (3), +.BR fopen (3), +.BR fread (3), +.BR fseek (3), +.BR getline (3), +.BR gets (3), +.BR getwchar (3), +.BR puts (3), +.BR scanf (3), +.BR ungetwc (3), +.BR unlocked_stdio (3), +.BR feature_test_macros (7) |