Tools for managing interprocess communication (IPC)

Modules
	Message Queues

	Shared Memory

Files
file	processInterface.hpp
	Process interface facilities.

file	sharedMemSegment.hpp
	Declarations for the mxlib shared memory facility.

file	processInterface.cpp
	Process interface facilities.

file	sharedMemSegment.cpp
	Definitions for the mxlib shared memory facility.

Macros
#define	MX_IPC_KEYLEN 1024
	The maximum length of the IPC key string.

#define	MX_IPC_PI_BUFSZ 128
	The process interface buffer size.

Functions
int	mx::ipc::command_response (const char cmd, char resp, size_t respsz)
	Run a process and copy the output to a string.

int	mx::ipc::runCommand (int &retVal, std::vector< std::string > &commandOutput, std::vector< std::string > &commandStderr, const std::vector< std::string > &commandList)
	Runs a command (with parameters) passed in using fork/exec.

Macro Definition Documentation

◆ MX_IPC_KEYLEN

#define MX_IPC_KEYLEN 1024

The maximum length of the IPC key string.

Definition at line 42 of file ipc.hpp.

◆ MX_IPC_PI_BUFSZ

#define MX_IPC_PI_BUFSZ 128

The process interface buffer size.

Definition at line 45 of file ipc.hpp.

Function Documentation

◆ command_response()

int mx::ipc::command_response	(	const char *	cmd,
		char *	resp,
		size_t	respsz
	)

Run a process and copy the output to a string.

Uses popen, so the attendant precautions about privileges apply.

Parameters

cmd	is the command to run
resp	is the string to copy the response to.
respsz	is the available size of the string.

Return values

0	on success
-1	on error

Definition at line 43 of file processInterface.cpp.

References MX_IPC_PI_BUFSZ.

◆ runCommand()

int mx::ipc::runCommand	(	int &	retVal,
		std::vector< std::string > &	commandOutput,
		std::vector< std::string > &	commandStderr,
		const std::vector< std::string > &	commandList
	)

Runs a command (with parameters) passed in using fork/exec.

A new process is fork()-ed, and the child runs execvp with command provided. The output of the process is captured in commandOutput, and error messages in commandStderr.

The process return value in retVal is only meaningful if this function returns 0.

If this function returns -1, the last entry in commandStderr will contain a message, and errno may be useful.

Returns: 0 on success; -1 on error

Parameters

[out]	retVal	the return value of the process. Only meaningful if this returns 0.
[out]	commandOutput	the output, line by line. If an error, first entry contains the message.
[out]	commandStderr	the output of stderr.
[in]	commandList	command to be run, with one entry per command line word

Definition at line 68 of file processInterface.cpp.

References MXE_PROCERR, mxError, and mxPError.

Referenced by mx::sys::gitRepo::getGitFileState(), mx::sys::gitRepo::getGitHash(), mx::sys::gitRepo::getGitModified(), and mx::sys::gitRepo::getGitName().

Modules

Files