blob: cd788d33f01b5c715098e42f58cafe1452ebac89 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
.TH LIBSIMPLE_GETENV_NE 3 2018-10-20 libsimple
.SH NAME
libsimple_getenv_ne \- get non-empty value of an environment variable
.SH SYNOPSIS
.nf
#include <libsimple.h>
static inline char *libsimple_getenv_ne(const char *\fIname\fP);
#ifndef getenv_ne
# define getenv_ne libsimple_getenv_ne
#endif
.fi
.PP
Link with
.IR \-lsimple .
.SH DESCRIPTION
The
.BR libsimple_getenv_ne ()
function searches the environment of the calling
process for the environment variable
.IR name .
If it exists, its value is returned unless the value
is the empty string.
.PP
Modifications to the environment variable made from
within the process, its parent, or other ancestor,
that have not be come visible to other process via
replacement of the process image, are visible to the
.BR libsimple_getenv_ne ()
function.
.SH RETURN VALUE
If the environment variable
.I name
is defined with a non-empty value, its value
is returned, otherwise
.B NULL
is returned.
.PP
The returned pointer must not be deallocated and
its content should not be modified. The returned
pointer becomes invalid when the environment variable
.I name
is unset or modified.
.SH ERRORS
The
.BR libsimple_getenv_ne ()
function cannot fail.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lb lb lb
l l l.
Interface Attribute Value
T{
.BR libsimple_getenv_ne ()
T} Thread safety MT-Safe env
T{
.BR libsimple_getenv_ne ()
T} Async-signal safety AS-Safe
T{
.BR libsimple_getenv_ne ()
T} Async-cancel safety AC-Safe
.TE
.SH EXAMPLES
None.
.SH APPLICATION USAGE
None.
.SH RATIONALE
None.
.SH FUTURE DIRECTIONS
None.
.SH NOTES
None.
.SH BUGS
None.
.SH SEE ALSO
.BR libsimple_getenv_e (3),
.BR getenv (3)
|
