QzshCheckShellCommand() - Find QSH Command
Syntax
#include <qshell.h>
int QzshCheckShellCommand( const char *command, const char *path );
Threadsafe: Yes
|
The QzshCheckShellCommand() function finds the
specified shell command by searching:
- for a built-in utility, then
- in each directory in the list specified by path or the
PATH environment variable in turn.
An application can use QzshCheckShellCommand()
to verify that command exists and the user has authority
to command before running it.
Parameters
*command
(Input) Pointer to null-terminated string that contains the shell
command to find.
*path
(Input) Pointer to null-terminated string that contains a colon
delimited list of directories to search. If this parameter is NULL,
QzshCheckShellCommand() uses the value of the
PATH environment variable.
Authorities
When command is an executable file, the user must have the
following authorities.
| Object Referred To |
Authority Required |
errno |
| Each directory in the path name preceding the executable
file |
*X |
EACCES |
| Executable file |
*X |
EACCES |
| If executable file is a shell script |
*RX |
EACCES |
Return value
- 0
- QzshCheckShellCommand() was successful. The
command was found in the current environment.
- -1
- Qp0zCheckShellCommand() was not successful.
The errno value is set to indicate the error.
Error conditions
If QzshCheckShellCommand() is not successful,
errno typically indicates one of the following errors. Under
some conditions, errno could indicate an error other than
those listed here.
- [EACCES]
- Permission denied.
- An attempt was made to access an object in a way forbidden by
its object access permissions.
- The thread does not have access to the specified file,
directory, component, or path.
- [EFAULT]
- The address used for an argument is not correct.
- In attempting to use an argument in a call, the system detected
an address that is not valid.
- While attempting to access a parameter passed to this function,
the system detected an address that is not valid.
- [EINVAL]
- The value specified for the argument is not correct.
- A function was passed incorrect argument values, or an
operation was attempted on an object and the operation specified is
not supported for that type of object.
- [ENOMEM]
- Storage allocation request failed.
- A function needed to allocate storage, but no storage is
available.
- There is not enough memory to perform the requested
function.
- [ENOENT]
- No such path or directory.
- The directory or component of the path name specified does not
exist.
- A named file or directory does not exist or is an empty
string.
- [EUNKNOWN]
- Unknown system state.
- The operation failed because of an unknown system state. See
any messages in the job log and correct any errors that are
indicated. Then retry the operation.
Related information
Example: Using the QzshCheckShellCommand()
function
For an example of using this function, see the QzshSystem() function.