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

.TH PUTC 3S 
.SH NAME
putc, putchar, fputc, putw \- put character or word on a stream
.SH SYNOPSIS
.B #include <stdio.h>
.PP
.B int putc(c, stream)
.br
.B char c;
.br
.SM
.B FILE
.B *stream;
.PP
.B putchar(c)
.PP
.B fputc(c, stream)
.br
.SM
.B FILE
.B *stream;
.PP
.B putw(w, stream)
.br
.SM
.B FILE
.B *stream;
.SH DESCRIPTION
.I Putc
appends the character
.I c
to the named output
.IR stream .
It returns the character written.
.PP
.I Putchar(c)
is defined as 
.I "putc(c, stdout)."
.PP
.I Fputc
behaves like 
.I putc,
but is a genuine function rather than a macro.
It may be used to save on object text.
.PP
.I Putw
appends word 
(i.e.
.BR int )
.I w
to the output
.IR stream .
It returns the word written.
.I Putw
neither assumes nor causes special alignment in the file.
.PP
The standard stream
.I stdout
is normally buffered if and only if the
output does not refer to a terminal;
this default may be changed by
.IR setbuf (3).
The standard stream
.I stderr
is by default unbuffered unconditionally,
but use of
.I freopen
(see
.IR fopen (3))
will cause it to become buffered;
.IR setbuf ,
again, will set the state to whatever is desired.
When an output stream is unbuffered information appears on the
destination file or terminal as soon as written;
when it is buffered many characters are saved up and written as a block.
.I Fflush
(see 
.IR fclose (3))
may be used to force the block out early.
.SH "SEE ALSO"
fopen(3), fclose(3), getc(3),
puts(3), printf(3),
fread(3)
.SH DIAGNOSTICS
These functions return the constant
.SM
.B EOF
upon error.
Since this is a good integer,
.IR  ferror (3)
should be used to detect 
.I putw
errors.
.SH BUGS
Because it is implemented as a macro,
.I putc
treats a
.I stream
argument with side effects improperly.
In particular
`putc(c, *f++);'
doesn't work sensibly.
Commit	Line	Data
187e2969 TL	1	.TH PUTC 3S
	2	.SH NAME
	3	putc, putchar, fputc, putw \- put character or word on a stream
	4	.SH SYNOPSIS
	5	.B #include <stdio.h>
	6	.PP
	7	.B int putc(c, stream)
	8	.br
	9	.B char c;
	10	.br
	11	.SM
	12	.B FILE
	13	.B *stream;
	14	.PP
	15	.B putchar(c)
	16	.PP
	17	.B fputc(c, stream)
	18	.br
	19	.SM
	20	.B FILE
	21	.B *stream;
	22	.PP
	23	.B putw(w, stream)
	24	.br
	25	.SM
	26	.B FILE
	27	.B *stream;
	28	.SH DESCRIPTION
	29	.I Putc
	30	appends the character
	31	.I c
	32	to the named output
	33	.IR stream .
	34	It returns the character written.
	35	.PP
	36	.I Putchar(c)
	37	is defined as
	38	.I "putc(c, stdout)."
	39	.PP
	40	.I Fputc
	41	behaves like
	42	.I putc,
	43	but is a genuine function rather than a macro.
	44	It may be used to save on object text.
	45	.PP
	46	.I Putw
	47	appends word
	48	(i.e.
	49	.BR int )
	50	.I w
	51	to the output
	52	.IR stream .
	53	It returns the word written.
	54	.I Putw
	55	neither assumes nor causes special alignment in the file.
	56	.PP
	57	The standard stream
	58	.I stdout
	59	is normally buffered if and only if the
	60	output does not refer to a terminal;
	61	this default may be changed by
	62	.IR setbuf (3).
	63	The standard stream
	64	.I stderr
65	is by default unbuffered unconditionally,
66	but use of
67	.I freopen
68	(see
69	.IR fopen (3))
70	will cause it to become buffered;
71	.IR setbuf ,
72	again, will set the state to whatever is desired.
73	When an output stream is unbuffered information appears on the
74	destination file or terminal as soon as written;
75	when it is buffered many characters are saved up and written as a block.
76	.I Fflush
77	(see
78	.IR fclose (3))
79	may be used to force the block out early.
80	.SH "SEE ALSO"
81	fopen(3), fclose(3), getc(3),
82	puts(3), printf(3),
83	fread(3)
84	.SH DIAGNOSTICS
85	These functions return the constant
86	.SM
87	.B EOF
88	upon error.
89	Since this is a good integer,
90	.IR ferror (3)
91	should be used to detect
92	.I putw
93	errors.
94	.SH BUGS
95	Because it is implemented as a macro,
96	.I putc
97	treats a
98	.I stream
99	argument with side effects improperly.
100	In particular
101	`putc(c, *f++);'
102	doesn't work sensibly.