libssh2_session_supported_algs(3)

1libssh2_session_supported_algs(3)   libssh2  libssh2_session_supported_algs(3)
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NAME

6       libssh2_session_supported_algs - get list of supported algorithms
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SYNOPSIS

9       #include <libssh2.h>
10
11       int
12       libssh2_session_supported_algs(LIBSSH2_SESSION* session,
13                                      int method_type,
14                                      const char*** algs);
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DESCRIPTION

17       session - An instance of initialized LIBSSH2_SESSION (the function will
18       use its pointer to the  memory  allocation  function).   method_type  -
19       Method  type.  See libssh2_session_method_pref(3).  algs - Address of a
20       pointer that will point to an array of returned algorithms
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22       Get a list of supported  algorithms  for  the  given  method_type.  The
23       method_type  parameter  is  equivalent  to  method_type in libssh2_ses‐
24       sion_method_pref(3). If successful, the function will allocate the  ap‐
25       propriate amount of memory. When not needed anymore, it must be deallo‐
26       cated by calling libssh2_free(3). When this function  is  unsuccessful,
27       this must not be done.
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29       In  order  to  get a list of all supported compression algorithms, lib‐
30       ssh2_session_flag(session, LIBSSH2_FLAG_COMPRESS, 1) must be called be‐
31       fore calling this function, otherwise only "none" will be returned.
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33       If  successful, the function will allocate and fill the array with sup‐
34       ported algorithms (the same names as defined in RFC 4253).   The  array
35       is not NULL terminated.
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EXAMPLE

38       #include "libssh2.h"
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40       const char **algorithms;
41       int rc, i;
42       LIBSSH2_SESSION *session;
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44       /* initialize session */
45       session = libssh2_session_init();
46       rc = libssh2_session_supported_algs(session,
47                                           LIBSSH2_METHOD_CRYPT_CS,
48                                           &algorithms);
49       if(rc > 0) {
50           /* the call succeeded, do sth. with the list of algorithms
51              (e.g. list them)... */
52           printf("Supported symmetric algorithms:\n");
53           for(i = 0; i < rc; i++)
54               printf("\t%s\n", algorithms[i]);
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56           /* ... and free the allocated memory when not needed anymore */
57           libssh2_free(session, algorithms);
58       }
59       else {
60           /* call failed, error handling */
61       }
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RETURN VALUE

64       On success, a number of returned algorithms (i.e a positive number will
65       be returned).  In case of a failure, an error code (a negative  number,
66       see below) is returned.  0 should never be returned.
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ERRORS

69       LIBSSH2_ERROR_BAD_USE - Invalid address of algs.
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71       LIBSSH2_ERROR_METHOD_NOT_SUPPORTED -  Unknown method type.
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73       LIBSSH2_ERROR_INVAL - Internal error (normally should not occur).
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75       LIBSSH2_ERROR_ALLOC - Allocation of memory failed.
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AVAILABILITY

78       Added in 1.4.0
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