[unix-history] / usr / man / man3 / getc.3s

.TH GETC 3S  "19 January 1983"
.SH NAME
getc, getchar, fgetc, getw \- get character or word from stream
.SH SYNOPSIS
.B #include <stdio.h>
.PP
.B int getc(stream)
.br
.SM
.B FILE
.B *stream;
.PP
.B int getchar()
.PP 
.B int fgetc(stream)
.br
.SM
.B FILE
.B *stream;
.PP
.B int getw(stream)
.br
.SM
.B FILE
.B *stream;
.SH DESCRIPTION
.I Getc
returns the next character from the named input
.IR stream .
.PP
.IR Getchar ()
is identical to 
.IR getc ( stdin ) .
.PP
.I Fgetc
behaves like 
.IR getc ,
but is a genuine function, not a macro;
it may be used to save object text.
.PP
.I Getw
returns the next
word (in a 32-bit integer on a VAX-11) from the named input
.IR stream .
It returns the constant
.SM
.B EOF
upon end of file or error, but since that is a good
integer value,
.I feof
and
.IR  ferror (3S)
should be used to check the success of
.IR getw .
.I Getw
assumes no special alignment in the file.
.SH "SEE ALSO"
fopen(3S),
putc(3S),
gets(3S),
scanf(3S),
fread(3S),
ungetc(3S)
.SH DIAGNOSTICS
These functions return the integer constant
.SM
.B EOF
at end of file or upon read error.
.PP
A stop with message,
`Reading bad file', means an attempt has been made to
read from a stream that has not been opened for
reading by
.IR fopen .
.SH BUGS
The end-of-file return from
.I getchar
is incompatible with that in UNIX editions 1-6.
.PP
Because it is implemented as a macro,
.I getc
treats a
.I stream
argument with side effects incorrectly.
In particular,
`getc(*f++);'
doesn't work sensibly.
Commit	Line	Data
4c178695 C	1	.TH GETC 3S "19 January 1983"
	2	.SH NAME
	3	getc, getchar, fgetc, getw \- get character or word from stream
	4	.SH SYNOPSIS
	5	.B #include <stdio.h>
	6	.PP
	7	.B int getc(stream)
	8	.br
	9	.SM
	10	.B FILE
	11	.B *stream;
	12	.PP
	13	.B int getchar()
	14	.PP
	15	.B int fgetc(stream)
	16	.br
	17	.SM
	18	.B FILE
	19	.B *stream;
	20	.PP
	21	.B int getw(stream)
	22	.br
	23	.SM
	24	.B FILE
	25	.B *stream;
	26	.SH DESCRIPTION
	27	.I Getc
	28	returns the next character from the named input
	29	.IR stream .
	30	.PP
	31	.IR Getchar ()
	32	is identical to
	33	.IR getc ( stdin ) .
	34	.PP
	35	.I Fgetc
	36	behaves like
	37	.IR getc ,
	38	but is a genuine function, not a macro;
	39	it may be used to save object text.
	40	.PP
	41	.I Getw
	42	returns the next
	43	word (in a 32-bit integer on a VAX-11) from the named input
	44	.IR stream .
	45	It returns the constant
	46	.SM
	47	.B EOF
	48	upon end of file or error, but since that is a good
	49	integer value,
	50	.I feof
	51	and
	52	.IR ferror (3S)
	53	should be used to check the success of
	54	.IR getw .
	55	.I Getw
	56	assumes no special alignment in the file.
	57	.SH "SEE ALSO"
	58	fopen(3S),
	59	putc(3S),
	60	gets(3S),
	61	scanf(3S),
	62	fread(3S),
	63	ungetc(3S)
	64	.SH DIAGNOSTICS
65	These functions return the integer constant
66	.SM
67	.B EOF
68	at end of file or upon read error.
69	.PP
70	A stop with message,
71	`Reading bad file', means an attempt has been made to
72	read from a stream that has not been opened for
73	reading by
74	.IR fopen .
75	.SH BUGS
76	The end-of-file return from
77	.I getchar
78	is incompatible with that in UNIX editions 1-6.
79	.PP
80	Because it is implemented as a macro,
81	.I getc
82	treats a
83	.I stream
84	argument with side effects incorrectly.
85	In particular,
86	`getc(*f++);'
87	doesn't work sensibly.