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C Library Reference
A
acl_to_text()
Convert an access control list (ACL) into text

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      - abort()
        Raise the SIGABRT signal to terminate program execution
      - abs()
        Return the absolute value of an integer
      - access()
        Check to see if a file or directory can be accessed
      - acl_add_perm()
        Add a permission to an access control list (ACL) permissions set
      - acl_calc_mask()
        Calculate the group class mask for an access control list (ACL)
      - acl_clear_perms()
        Clear all permissions from an ACL permissions set
      - acl_copy_entry()
        Copy the contents of one ACL entry into another
      - acl_copy_ext()
        Copy an ACL from system space to user space
      - acl_copy_int()
        Copy an ACL from user space to system space
      - acl_create_entry()
        Create an entry in an access control list
      - acl_delete_entry()
        Delete an entry from an access control list (ACL)
      - acl_delete_perm()
        Delete a permission from an ACL permissions set
      - acl_dup()
        Duplicate an access control list (ACL) in a working storage area
      - acl_free()
        Free the working storage area allocated for an access control list (ACL) data object
      - acl_from_text()
        Create an access control list (ACL) from text
      - acl_get_entry()
        Get an entry in an access control list (ACL)
      - acl_get_fd()
        Get the access control list associated with a file descriptor
      - acl_get_file()
        Get the ACL for a given path
      - acl_get_perm_np()
        Test whether a given permission is present in an ACL permissions set
      - acl_get_permset()
        Get a permissions set from an ACL entry
      - acl_get_qualifier()
        Get the qualifier from an ACL entry
      - acl_get_tag_type()
        Get the type of tag from an ACL entry
      - acl_init()
        Allocate and initialize an access control list (ACL) working storage area
      - acl_set_fd()
        Set the access ACL for the object associated with a file descriptor
      - acl_set_file()
        Set the access control list for a path
      - acl_set_permset()
        Set the permissions set in an ACL entry
      - acl_set_qualifier()
        Set the qualifier for an ACL entry
      - acl_set_tag_type()
        Set the tag type of an ACL entry
      - acl_size()
        Determine the size of the external form of an ACL
      - acl_to_text()
        Convert an access control list (ACL) into text
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        Validate an access control list (ACL)
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        Display a diagnostic message and optionally terminate the program
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        Safely add to a variable, returning the previous value (QNX OS)
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        Safely clear bits in a variable (QNX OS)
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        Safely clear bits in a variable, returning the previous value (QNX OS)
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acl_to_text()

QNX SDP8.0C Library ReferenceAPIDeveloper

Convert an access control list (ACL) into text

Synopsis:

#include <sys/acl.h>

char *acl_to_text( acl_t acl,
                   ssize_t *len_p );

Arguments:

acl: A pointer to the ACL that you want to convert into text.
len_p: NULL, or a pointer to a location where the function can store the length of the string (not including the terminating null character).

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The acl_to_text() function converts an access control list into the long text form:

tag_type:qualifier:permissions

The tag_type is user, group, other, or mask, the qualifier is the name or numeric ID of a user or group, and the permissions are in the form rwx, with a hyphen (-) replacing any permissions that aren't granted.

When you're finished with the text form of the ACL, you should call acl_free() to release it.

Returns:

A pointer to the text form of the ACL, or NULL if an error occurred (errno is set).

Errors:

EINVAL: The acl argument doesn't point to a valid ACL, or the ACL contains some improperly formed entries or otherwise can't be converted.
ENOMEM: There wasn't enough memory available to allocate for the string.

Classification:

This function is based on the withdrawn POSIX draft P1003.1e.


Safety:
Cancellation point	No
Signal handler	No
Thread	Yes

Page updated: August 09, 2024