---
name: "putpwent"
section: "3"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/putpwent"
---

# putpwent(3)

write a password file entry

## NAME

putpwent - write a password file entry

## LIBRARY

Standard C library (*libc*, *-lc*)

## SYNOPSIS

```
#include <stdio.h>
#include <sys/types.h>
#include <pwd.h>
```

**int putpwent(const struct passwd \*restrict** *p***, FILE \*restrict** *stream***);**

Feature Test Macro Requirements for glibc (see [**feature\_test\_macros**(7)](/feature_test_macros/7.md)):

**putpwent**():

```
    Since glibc 2.19:
        _DEFAULT_SOURCE
    glibc 2.19 and earlier:
        _SVID_SOURCE
```

## DESCRIPTION

The **putpwent**() function writes a password entry from the structure *p* in the file associated with *stream*.

The *passwd* structure is defined in *\<pwd.h\>* as follows:

```
struct passwd {
    char    *pw_name;        /* username */
    char    *pw_passwd;      /* user password */
    uid_t    pw_uid;         /* user ID */
    gid_t    pw_gid;         /* group ID */
    char    *pw_gecos;       /* real name */
    char    *pw_dir;         /* home directory */
    char    *pw_shell;       /* shell program */
};
```

## RETURN VALUE

The **putpwent**() function returns 0 on success. On failure, it returns -1, and *errno* is set to indicate the error.

## ERRORS

- **EINVAL**

  Invalid (NULL) argument given.

## ATTRIBUTES

For an explanation of the terms used in this section, see [**attributes**(7)](/attributes/7.md).

| | | |
| --- | --- | --- |
| **Interface** | **Attribute** | **Value** |
| **putpwent**() | Thread safety | MT-Safe locale |

## STANDARDS

None.

## HISTORY

SVr4.

## SEE ALSO

[**endpwent**(3)](/endpwent/3.md), [**fgetpwent**(3)](/fgetpwent/3.md), [**getpw**(3)](/getpw/3.md), [**getpwent**(3)](/getpwent/3.md), [**getpwnam**(3)](/getpwnam/3.md), [**getpwuid**(3)](/getpwuid/3.md), [**setpwent**(3)](/setpwent/3.md)