xref: /illumos-gate/usr/src/man/man3c/getenv.3c (revision bbf21555)
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GETENV 3C "Jul 24, 2002"
NAME
getenv - return value for environment name
SYNOPSIS

#include <stdlib.h>

char *getenv(const char *name);
DESCRIPTION

The getenv() function searches the environment list (see environ(7)) for a string of the form name=value and, if the string is present, returns a pointer to the value in the current environment.

RETURN VALUES

If successful, getenv() returns a pointer to the value in the current environment; otherwise, it returns a null pointer.

USAGE

The getenv() function can be safely called from a multithreaded application. Care must be exercised when using both getenv() and putenv(3C) in a multithreaded application. These functions examine and modify the environment list, which is shared by all threads in an application. The system prevents the list from being accessed simultaneously by two different threads. It does not, however, prevent two threads from successively accessing the environment list using getenv() or putenv(3C).

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Standard
MT-Level Safe
SEE ALSO

exec (2), putenv (3C), attributes (7), environ (7), standards (7)