name , const char * value , int overwrite ); int unsetenv(const char * name ); Feature Test Macro Requirements ... glibc (see feature_test_macros (7)): setenv (), unsetenv (): _POS…name , const char * value , int overwrite ); int unsetenv(const char * name ); Feature Test Macro Requirements ... glibc (see feature_test_macros (7)): setenv (), unsetenv (): _POS…getenv (), putenv (3), setenv (3), or unsetenv (3). The "secure execution" mode of secure_getenv ... getauxval (3), putenv (3), setenv (3), unsetenv (3), capabilities (7), environgetenv (), putenv (3), setenv (3), or unsetenv (3). The "secure execution" mode of secure_getenv ... getauxval (3), putenv (3), setenv (3), unsetenv (3), capabilities (7), environALSO clearenv (3), getenv (3), setenv (3), unsetenv (3), environ