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sizeof_proplist_entry(3) [osf1 man page]

sizeof_proplist_entry(3)				     Library Functions Manual					  sizeof_proplist_entry(3)

NAME
sizeof_proplist_entry - Determines space necessary to store an Extended File Attribute SYNOPSIS
#include <sys/proplist.h> int sizeof_proplist_entry ( char *name, int value_size ); PARAMETERS
A null terminated ASCII string, pointing to the Extended File Attribute name. Specifies the size in bytes of the Extended File Attribute value. DESCRIPTION
The sizeof_proplist_entry function determines the minimum size of the Extended File Attribute buffer required to store an Extended File Attribute, specified by the *name and value_size parameters. An Extended File Attribute is a name and value pair that is contained in a variable-sized structure called a Property List. A Property List is part of a file's metadata and can contain abstract name and value pairs (Extended File Attributes) that can be set either by the operating system (for example, ACLs and privileges) or by a user-level application (for example, PC File Attributes). Although not a requirement, you should use the sizeof_proplist_entry(3) and add_proplist_entry(3) functions to initialize the Extended File Attribute buffer passed to setproplist(3) and fsetproplist(3). EXAMPLES
#include <sys/proplist.h> main() { char *ptr, *buf, *name, *value; int *value_len, *flags, buffer_size, min_buffer_size, ret, nbytes; struct pro- plistname_args; static char *names[] = { "primary_name", "secondary_name", "" }; /* * How big a buffer do I need to store my name and value * pair in a property list ? */ buffer_size = sizeof_proplist_entry("primary_name", 18); buffer_size += sizeof_proplist_entry("secondary_name", 13); . . . RETURN VALUES
If successful, the function returns the minimum number of bytes required to store the specified name and value pair in an Extended File Attribute buffer. RELATED INFORMATION
Functions: add_proplist_entry(3), delproplist(3), fdelproplist(3), fgetproplist(3), fsetproplist(3), get_proplist_entry(3), getproplist(3), setproplist(3), sizeof_proplist_entry(3). Files: proplist(4), sys/proplist.h. delim off sizeof_proplist_entry(3)

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getproplist(3)						     Library Functions Manual						    getproplist(3)

NAME
getproplist, fgetproplist - Gets the Extended File Attributes of a file SYNOPSIS
#include <sys/proplist.h> int getproplist ( char *path, int follow, struct proplistname_args *args, int nbytes, char *buf, int *min_buf_size ); int fgetproplist ( int fd, struct proplistname_args *args, int nbytes, char *buf, int *min_buf_size ); PARAMETERS
Points to a file whose Extended File Attributes are to be retrieved from its Property List. If non-zero, specifies that if the last component in *path is a symbolic link, then the link should be traversed. Points to the proplistname_args structure, defined in sys/proplist.h, that contains the following members: pl_mask Contains system-wide Extended File Attributes. Note that if you are retrieving all the Extended File Attributes of a file, pl_mask must equal PLE_FLAG_ALL defined in sys/pro- plist.h. Also, if you are copying Extended File Attribute flags that match certain system-wide Extended File Attributes, the value of pl_mask should be formed by ORing the desired values of the system-wide Extended File Attributes. pl_numnames Contains the number of Extended File Attributes names held in the names array, pl_names. pl_names Contains a counted array of Extended File Attribute names. Note that the Extended File Attribute names are null terminated ASCII strings and that the last element of the array must be a null pointer. Also, a null array pointer indicates all Extended File Attributes. Specifies the size of the Extended File Attribute buffer in bytes. Points to the buffer that holds the Extended File Attributes. Points to the buffer that holds the status of the size of the Extended File Attribute. Specifies a file descriptor for a file whose Extended File Attributes are to be retrieved from its Property List. This parameter is used with the fgetproplist function. DESCRIPTION
The getproplist function gets the Extended File Attributes of a file pointed to by *path and places them in the Extended File Attribute buffer pointed to by nbytes. Which Extended File Attributes will be retrieved is determined by the parameters from the structure proplist- name_args, defined in sys/proplist.h, that are passed to *args. An Extended File Attribute is a name and value pair that is contained in a variable-sized structure called a Property List. A Property List is part of a file's metadata and can contain abstract name and value pairs (Extended File Attributes) that can be set either by the operating system (for example, ACLs and privileges) or by a user-level application (for example, PC File Attributes). The fgetproplist function behaves the same as getproplist, except that it operates on a file descriptor rather than a pointer to a file. NOTES
Although not a requirement, you should use the get_proplist_entry(3) function to parse the attribute buffer returned by getproplist and fgetproplist. EXAMPLES
#include <sys/proplist.h> main() { char *ptr, *buf, *name, *value; int *value_len, *flags, buffer_size, min_buffer_size, ret, nbytes; struct pro- plistname_args getargs; static char *names[] = { "primary_name", "secondary_name", "" }; /* * Malloc the buffer */ buffer_size = 8192 buf = ptr = (char *)malloc(buffer_size); . . . again: /* * Call the system call to load buffer with property list * entries. */ ret = getproplist("/tmp/foo", &getargs, buffer_size, buf, &min_buffer_size); if (ret < 0) { perror("getproplist"); free(buf); exit(1); } /* * If buffer_size is not sufficient to store the name and value * pairs, malloc a bigger buffer and try again. */ if (ret == 0 && min_buffer_size) { free(buf); buf = (char *)malloc(min_buffer_size); buffer_size = min_buffer_size; goto again; } /* * Buffer contains ret bytes of name and value pairs */ ptr = buf; while (ret > 0) { /* * Call getproplist_entry to initialize name and value * pointers to entries position within buffer. */ ret -= get_proplist_entry(&name, &flags, &value_len, &value, &ptr); printf("name %s value len %d value %s0, name, *value_len, value); } . . . RETURN VALUES
If the function is successful, a value greater than zero is returned, which indicates the number of bytes of the Extended File Attribute that were copied into nbytes. In addition, the intersection between the Extended File Attributes associated with the file pointed to by *path and the Extended File Attribute names specified in the expression args->pl_names are also returned. If the function is not successful, one of the following values is returned: Zero A return value of zero indicates that one of the following conditions apply, depending on the value of the parameter *buf: *buf is zero If *buf is zero, the intersection between the Extended File Attributes associated with the file pointed to by *path and the Extended File Attribute names specified in the expression args->pl_names was a null set. *buf is greater than zero If *buf is greater than zero, the size of the Extended File Attribute buffer specified by the parameter *args was insufficient to hold the intersection between the Extended File Attributes associated with the file pointed to by *path and the Extended File Attribute names specified in the parameter args->pl_names. Note that the value contained in *buf is the number of bytes required to retrieve successfully the requested Extended File Attributes. The integer -1 If the integer -1 is returned, the function was unsuccessful and errno is set to indicate the error. ERRORS
In addition to errors associated with open(2), the function will fail if: Search permission was denied for a directory in *path. A problem was encountered with the Extended File Attribute. A problem was encountered with the Extended File Attribute. There was an error reading some portion of the Property List. The Extended File Attribute could not be associated with the file pointed to by *path. The calling program does ot have the appropriate system priviliges to access the requested Extended File Attribute, for example, DEC_AUDIT_PROPLIST- FLAG. RELATED INFORMATION
Functions: open(2), add_proplist_entry(3), delproplist(3), fdelproplist(3), fgetproplist(3), fsetproplist(3), get_proplist_entry(3), get- proplist(3), setproplist(3), sizeof_proplist_entry(3). Files: proplist(4), sys/proplist.h. delim off getproplist(3)
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