(mozilla-projects-nss-reference-nss-initialize)=

# NSS_Initialize

## [Name](#name)

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NSS_Initialize - initialize NSS.
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## [Syntax](#syntax)

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```{code}
SECStatus NSS_Initialize(const char *configdir,
                         const char *certPrefix,
                         const char *keyPrefix,
                         const char *secmodName,
                         PRUint32 flags);
```

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## [Parameters](#parameters)

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`NSS_Initialize` has five parameters:

`configdir`

: [in] the directory where the certificate, key, and module databases live. To-do: document the
  "sql:" prefix.

`certPrefix`

: [in] prefix added to the beginning of the certificate database, for example, "https-server1-".

`keyPrefix`

: [in] prefix added to the beginning of the key database, for example, "https-server1-".

`secmodName`

: [in] name of the security module database, usually "secmod.db".

`flags`

: [in] bit flags that specify how NSS should be initialized.
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## [Description](#description)

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`NSS_Initialize` initializes NSS. It is more flexible than `NSS_Init`, `NSS_InitReadWrite`,
and `NSS_NoDB_Init`. If any of those simpler NSS initialization functions suffices for your
needs, call that instead.

The `flags` parameter is a bitwise OR of the following flags:

- NSS_INIT_READONLY - Open the databases read only.
- NSS_INIT_NOCERTDB - Don't open the cert DB and key DB's, just initialize the volatile certdb.
- NSS_INIT_NOMODDB - Don't open the security module DB, just initialize the PKCS #11 module.
- NSS_INIT_FORCEOPEN - Continue to force initializations even if the databases cannot be opened.
- NSS_INIT_NOROOTINIT - Don't try to look for the root certs module automatically.
- NSS_INIT_OPTIMIZESPACE - Optimize for space instead of speed. Use smaller tables and caches.
- NSS_INIT_PK11THREADSAFE - only load PKCS#11 modules that are thread-safe, i.e., that support
  locking - either OS locking or NSS-provided locks . If a PKCS#11 module isn't thread-safe,
  don't serialize its calls; just don't load it instead. This is necessary if another piece of
  code is using the same PKCS#11 modules that NSS is accessing without going through NSS, for
  example, the Java SunPKCS11 provider.
- NSS_INIT_PK11RELOAD - ignore the CKR_CRYPTOKI_ALREADY_INITIALIZED error when loading PKCS#11
  modules. This is necessary if another piece of code is using the same PKCS#11 modules that NSS
  is accessing without going through NSS, for example, Java SunPKCS11 provider.
- NSS_INIT_NOPK11FINALIZE - never call C_Finalize on any PKCS#11 module. This may be necessary
  in order to ensure continuous operation and proper shutdown sequence if another piece of code
  is using the same PKCS#11 modules that NSS is accessing without going through NSS, for
  example, Java SunPKCS11 provider. The following limitation applies when this is set
  \: SECMOD_WaitForAnyTokenEvent will not use C_WaitForSlotEvent, in order to prevent the need
  for C_Finalize. This call will be emulated instead.
- NSS_INIT_RESERVED - Currently has no effect, but may be used in the future to trigger better
  cooperation between PKCS#11 modules used by both NSS and the Java SunPKCS11 provider. This
  should occur after a new flag is defined for C_Initialize by the PKCS#11 working group.
- NSS_INIT_COOPERATE - Sets the above four recommended options for applications that use both
  NSS and the Java SunPKCS11 provider.
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## [Return value](#return_value)

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`NSS_Initialize` returns SECSuccess on success, or SECFailure on failure.
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## [Examples](#examples)

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```{code}
#include <nss.h>

SECStatus rv;
const char *configdir;

configdir = ...;  /* application-specific */
rv = NSS_Initialize(configdir, "", "", SECMOD_DB, NSS_INIT_NOROOTINIT | NSS_INIT_OPTIMIZESPACE);
```

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## [See also](#see_also)

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- NSS_Init, NSS_InitReadWrite, NSS_NoDB_Init, NSS_Shutdown
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