|GETENV(3)||Linux Programmer's Manual||GETENV(3)|
NAMEgetenv, secure_getenv - get an environment variable
char *getenv(const char * name );
char *secure_getenv(const char *name);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
DESCRIPTIONThe getenv() function searches the environment list to find the environment variable name, and returns a pointer to the corresponding value string.
- the process's effective user ID did not match its real user ID or the process's effective group ID did not match its real group ID (typically this is the result of executing a set-user-ID or set-group-ID program);
- the effective capability bit was set on the executable file; or
- the process has a nonempty permitted capability set.
Secure execution may also required if triggered by some Linux security modules.
The secure_getenv() function is intended for use in general-purpose libraries to avoid vulnerabilities that could occur if set-user-ID or set-group-ID programs accidentally trusted the environment.
RETURN VALUEThe getenv() function returns a pointer to the value in the environment, or NULL if there is no match.
VERSIONSsecure_getenv() first appeared in glibc 2.17.
CONFORMING TOgetenv(): SVr4, POSIX.1-2001, 4.3BSD, C89, C99.
NOTESThe strings in the environment list are of the form name=value.
SEE ALSOclearenv(3), getauxval(3), putenv(3), setenv(3), unsetenv(3), capabilities(7), environ(7)
COLOPHONThis page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.