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697650caa9
This is mostly mechanical change initializing all the pointers I was able to
find with some grep and manual review of sources and examples.
Used the following greps (which yield some false positives though):
git grep " \w* *\* *\w*;$"
git grep " ssh_session \w*;"
git grep " ssh_channel \w*;"
git grep " struct ssh_iterator \*\w*;"
git grep " ssh_bind \w*;"
git grep " ssh_key \w*;"
git grep " ssh_string \w*;"
git grep " ssh_buffer \w*;"
git grep " HMACCTX \w*;"
git grep " SHACTX \w*;"
grep -rinP '^(?!.*=)\s*(?:\w+\s+)*\w+\s*\*\s*\w+\s*;'
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
95 lines
2.3 KiB
Plaintext
95 lines
2.3 KiB
Plaintext
/**
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@page libssh_tutor_command Chapter 4: Passing a remote command
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@section remote_command Passing a remote command
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Previous chapter has shown how to open a full shell session, with an attached
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terminal or not. If you only need to execute a command on the remote end,
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you don't need all that complexity.
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The method described here is suited for executing only one remote command.
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If you need to issue several commands in a row, you should consider using
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a non-interactive remote shell, as explained in previous chapter.
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@see shell
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@subsection exec_remote Executing a remote command
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The first steps for executing a remote command are identical to those
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for opening remote shells. You first need a SSH channel, and then
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a SSH session that uses this channel:
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@code
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int show_remote_files(ssh_session session)
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{
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ssh_channel channel = NULL;
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int rc;
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channel = ssh_channel_new(session);
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if (channel == NULL) return SSH_ERROR;
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rc = ssh_channel_open_session(channel);
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if (rc != SSH_OK)
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{
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ssh_channel_free(channel);
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return rc;
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}
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@endcode
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Once a session is open, you can start the remote command with
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ssh_channel_request_exec():
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@code
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rc = ssh_channel_request_exec(channel, "ls -l");
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if (rc != SSH_OK)
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{
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ssh_channel_close(channel);
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ssh_channel_free(channel);
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return rc;
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}
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@endcode
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If the remote command displays data, you get them with ssh_channel_read().
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This function returns the number of bytes read. If there is no more
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data to read on the channel, this function returns 0, and you can go to next step.
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If an error has been encountered, it returns a negative value:
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@code
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char buffer[256];
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int nbytes;
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nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
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while (nbytes > 0)
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{
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if (fwrite(buffer, 1, nbytes, stdout) != nbytes)
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{
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ssh_channel_close(channel);
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ssh_channel_free(channel);
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return SSH_ERROR;
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}
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nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
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}
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if (nbytes < 0)
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{
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ssh_channel_close(channel);
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ssh_channel_free(channel);
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return SSH_ERROR;
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}
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@endcode
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Once you read the result of the remote command, you send an
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end-of-file to the channel, close it, and free the memory
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that it used:
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@code
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ssh_channel_send_eof(channel);
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ssh_channel_close(channel);
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ssh_channel_free(channel);
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return SSH_OK;
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}
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@endcode
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*/
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