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

.TH STDIO 3S 
.SH NAME
stdio \- standard buffered input/output package
.SH SYNOPSIS
.B #include <stdio.h>
.PP
.SM
.B FILE
.B *stdin;
.br
.SM
.B FILE
.B *stdout;
.br
.SM
.B FILE
.B *stderr;
.SH DESCRIPTION
The functions described in Sections 3S constitute an efficient
user-level buffering scheme.
The in-line macros
.I getc
and
.IR  putc (3)
handle characters quickly.
The higher level routines
.I "gets, fgets, scanf, fscanf, fread,"
.I "puts, fputs, printf, fprintf, fwrite"
all use
.I getc
and
.I putc;
they can be freely intermixed.
.PP
A file with associated buffering is called a
.I stream,
and is declared to be a pointer to a defined type
.SM
.B FILE.
.IR  Fopen (3)
creates certain descriptive data for a stream
and returns a pointer to designate the stream in all
further transactions.
There are three normally open streams with constant
pointers declared in
the include file and associated with the standard open files:
.TP 10n
.BR stdin
standard input file
.br
.ns
.TP
.B stdout
standard output file
.br
.ns
.TP
.BR stderr
standard error file
.PP
A constant `pointer'
.SM
.B NULL
(0)
designates no stream at all.
.PP
An integer constant
.SM
.B EOF
(\-1) is returned
upon end of file or error by integer functions that
deal with streams.
.PP
Any routine that uses the standard input/output package
must include the header file <stdio.h> of pertinent
macro definitions.
The functions and constants mentioned in sections labeled 3S
are declared in the include file
and need no further declaration.
The constants, and the following `functions' are
implemented as macros; redeclaration of these names
is perilous:
.I getc,
.I getchar,
.I putc,
.I putchar,
.I feof,
.I ferror,
.IR fileno .
.SH "SEE ALSO"
open(2), close(2), read(2), write(2)
.SH DIAGNOSTICS
The value
.SM
.B EOF
is returned uniformly to indicate that a
.SM
.B FILE
pointer has not been initialized with
.I fopen,
input (output) has been attempted on an output (input) stream,
or a
.SM
.B FILE
pointer designates corrupt or otherwise unintelligible
.SM
.B FILE
data.
Commit	Line	Data
c4665c80 TL	1	.TH STDIO 3S
	2	.SH NAME
	3	stdio \- standard buffered input/output package
	4	.SH SYNOPSIS
	5	.B #include <stdio.h>
	6	.PP
	7	.SM
	8	.B FILE
	9	.B *stdin;
	10	.br
	11	.SM
	12	.B FILE
	13	.B *stdout;
	14	.br
	15	.SM
	16	.B FILE
	17	.B *stderr;
	18	.SH DESCRIPTION
	19	The functions described in Sections 3S constitute an efficient
	20	user-level buffering scheme.
	21	The in-line macros
	22	.I getc
	23	and
	24	.IR putc (3)
	25	handle characters quickly.
	26	The higher level routines
	27	.I "gets, fgets, scanf, fscanf, fread,"
	28	.I "puts, fputs, printf, fprintf, fwrite"
	29	all use
	30	.I getc
	31	and
	32	.I putc;
	33	they can be freely intermixed.
	34	.PP
	35	A file with associated buffering is called a
	36	.I stream,
	37	and is declared to be a pointer to a defined type
	38	.SM
	39	.B FILE.
	40	.IR Fopen (3)
	41	creates certain descriptive data for a stream
	42	and returns a pointer to designate the stream in all
	43	further transactions.
	44	There are three normally open streams with constant
	45	pointers declared in
	46	the include file and associated with the standard open files:
	47	.TP 10n
	48	.BR stdin
	49	standard input file
	50	.br
	51	.ns
	52	.TP
	53	.B stdout
	54	standard output file
	55	.br
	56	.ns
	57	.TP
	58	.BR stderr
	59	standard error file
	60	.PP
	61	A constant `pointer'
	62	.SM
	63	.B NULL
	64	(0)
65	designates no stream at all.
66	.PP
67	An integer constant
68	.SM
69	.B EOF
70	(\-1) is returned
71	upon end of file or error by integer functions that
72	deal with streams.
73	.PP
74	Any routine that uses the standard input/output package
75	must include the header file <stdio.h> of pertinent
76	macro definitions.
77	The functions and constants mentioned in sections labeled 3S
78	are declared in the include file
79	and need no further declaration.
80	The constants, and the following `functions' are
81	implemented as macros; redeclaration of these names
82	is perilous:
83	.I getc,
84	.I getchar,
85	.I putc,
86	.I putchar,
87	.I feof,
88	.I ferror,
89	.IR fileno .
90	.SH "SEE ALSO"
91	open(2), close(2), read(2), write(2)
92	.SH DIAGNOSTICS
93	The value
94	.SM
95	.B EOF
96	is returned uniformly to indicate that a
97	.SM
98	.B FILE
99	pointer has not been initialized with
100	.I fopen,
101	input (output) has been attempted on an output (input) stream,
102	or a
103	.SM
104	.B FILE
105	pointer designates corrupt or otherwise unintelligible
106	.SM
107	.B FILE
108	data.