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.TH FGETC 2

.SH NAME

fgetc, getc, getchar, fputc, putc, putchar, ungetc, fgets, gets, fputs, puts, fread, fwrite \- Stdio input and output

.SH SYNOPSIS

.B #include <u.h>

.br

.B #include <stdio.h>

.ta \w'\fLlong 'u

.PP

.B

int	fgetc(FILE *f)

.PP

.B

int	getc(FILE *f)

.PP

.B

int	getchar(void)

.PP

.B

int	fputc(int c, FILE *f)

.PP

.B

int	putc(int c, FILE *f)

.PP

.B

int	putchar(int c)

.PP

.B

int	ungetc(int c, FILE *f)

.PP

.B

char	*fgets(char *s, int n, FILE *f)

.PP

.B

char	*gets(char *s)

.PP

.B

int	fputs(char *s, FILE *f)

.PP

.B

int	puts(char *s)

.PP

.B

long	fread(void *ptr, long itemsize, long nitems, FILE *stream)

.PP

.B

long	fwrite(void *ptr, long itemsize, long nitems, FILE *stream)

.SH DESCRIPTION

The functions described here work on open Stdio streams (see

.IR fopen ).

.PP

.I Fgetc

returns as an

.B int

the next

.B unsigned

.B char

from input stream

.IR f .

If the stream is at end-of-file, the end-of-file indicator for the

stream is set and

.I fgetc

returns

.BR EOF .

If a read error occurs, the error indicator for the stream is set and

.I fgetc

returns

.BR EOF .

.I Getc

is like

.I fgetc

except that it is implemented as a macro.

.I Getchar

is like

.I getc

except that it always reads from

.BR stdin .

.PP

.I Ungetc

pushes character

.I c

back onto the input stream

.BR f .

The pushed-back character will be returned by subsequent reads in

the reverse order of their pushing.

A successful intervening

.IR fseek ,

.IR fsetpos ,

or

.I rewind

on

.I f

discards any pushed-back characters for

.IR f .

One character of push-back is guaranteed.

.I Ungetc

returns the character pushed back (converted to

.B unsigned

.BR char ),

or

.B EOF

if the operation fails.

A successful call to

.I ungetc

clears the end-of-file indicator for the stream.

The file position indicator for the stream after reading or discarding

all pushed-back characters is the same as it was before the

characters were pushed back.

.PP

.I Fputc

writes character

.I c

(converted to

.B unsigned

.BR char )

to output stream

.IR f

at the position indicated by the position indicator for the stream

and advances the indicator appropriately.

If the file cannot support positioning requests, or if the stream was

opened with append mode, the character is appended to the output stream.

.I Fputc

returns the character written or

.B EOF

if there was a write error.

.I Putc

is like

.IR fputc

but is implemented as a macro.

.I Putchar

is like

.I putc

except that it always writes to

.BR stdout .

.PP

All other input takes place as if characters were read by successive

calls to

.I fgetc

and all other output takes place as if characters were written by

successive calls to

.IR fputc .

.PP

.I Fgets

reads up to and including the next newline, but not past end-of-file

or more than

.IR n -1

characters, from stream

.I f

into array

.IR s .

A null character is written immediately after the last character read

into the array (if any characters are read at all).

.I Fgets

returns

.I s

if successful, otherwise a null pointer.

.I Gets

is similar to

.IR fgets

except that it always reads from

.B stdin

and it discards the terminating newline, if any.

.I Gets

does not check for overflow of the receiving array, so its use is deprecated.

.PP

.I Fputs

writes the string

.I s

to  stream

.IR f ,

returning

.B EOF

if a write error occurred, otherwise a nonnegative value.

The terminating null character is not written.

.I Puts

is the same, writing to

.BR stdout .

.PP

.I Fread

reads from the named input

.IR stream 

at most

.I nitems

of data of size

.I itemsize

and the type of

.I *ptr

into a block beginning at

.IR ptr .

It returns the number of items actually read.

.PP

.I Fwrite

appends to the named output

.I stream

at most

.I nitems

of data of size

.I itemsize

and the type of

.I *ptr

from a block beginning at

.IR ptr .

It returns the number of items actually written.

.SH SOURCE

.B /sys/src/libstdio

.SH "SEE ALSO"

.IR read (2), 

.IR fopen (2),

.IR bio (2)

.SH BUGS

Stdio does not handle

.SM UTF

or runes; use Bio instead.