isencrypt(3GEN) String Pattern-Matching Library Functions isencrypt(3GEN)NAMEisencrypt - determine whether a buffer of characters is encrypted
SYNOPSIS
cc [flag...] [file...] -lgen [library...]
#include<libgen.h>
int isencrypt(const char *fbuf, size_t ninbuf);
DESCRIPTIONisencrypt() uses heuristics to determine whether a buffer of characters
is encrypted. It requires two arguments: a pointer to an array of char‐
acters and the number of characters in the buffer.
isencrypt() assumes that the file is not encrypted if all the charac‐
ters in the first block are ASCII characters. If there are non-ASCII
characters in the first ninbuf characters, and if the setlocale()
LC_CTYPE category is set to C or ascii, isencrypt() assumes that the
buffer is encrypted
If the LC_CTYPE category is set to a value other than C or ascii, then
isencrypt() uses a combination of heuristics to determine if the buffer
is encrypted. If ninbuf has at least 64 characters, a chi-square test
is used to determine if the bytes in the buffer have a uniform distri‐
bution; if it does, then isencrypt() assumes the buffer is encrypted.
If the buffer has less than 64 characters, a check is made for null
characters and a terminating new-line to determine whether the buffer
is encrypted.
RETURN VALUES
If the buffer is encrypted, 1 is returned; otherwise, zero is
returned.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOsetlocale(3C), attributes(5)NOTES
When compiling multithreaded applications, the _REENTRANT flag must be
defined on the compile line. This flag should only be used in multi‐
threaded applications.
SunOS 5.10 29 Dec 1996 isencrypt(3GEN)
