process.h

A simple one header solution to launching processes and interacting with them for C/C++.

Usage

Just include process.h in your code!

The current supported compilers are gcc, clang and msvc.

The current supported platforms are Linux, Mac OSX and Windows.

Design

Process is a single header cross-platform library that allows users to launch processes, interact with the stdin, stdout, and stderr of the process, and wait for the process to complete.

Launching a Process

To launch a process you call process_create like so:

const char *command_line[] = {"echo", "\"Hello, world!\"", NULL};
struct process_s process;
int result = process_create(command_line, 0, &process);
if (0 != result) {
  // an error occurred!
}

You specify an array of string for the command line - terminating the array with a NULL element.

If the process is created successfully then 0 is returned from process_create.

Writing to the Standard Input of a Process

To write to the standard input of a child process you call process_stdin to get the FILE handle to write with, passing a previously created process, like so:

FILE* p_stdin = process_stdin(&process);
fputs("Hello, world!", p_stdin);

Care must be taken to not write to the stdin after any call to process_join or process_destroy.

Reading from the Standard Output of a Process

To read from the standard output of a child process you call process_stdout to get the FILE handle to read with, passing a previously created process, like so:

FILE* p_stdout = process_stdout(&process);
char hello_world[32];
fgets(hello_world, 32, p_stdout);

Care must be taken to not read from the stdout after any call to process_destroy.

Reading from the Standard Error of a Process

To read from the standard error of a child process you call process_stderr to get the FILE handle to read with, passing a previously created process, like so:

FILE* p_stderr = process_stderr(&process);
char hello_world[32];
fgets(hello_world, 32, p_stderr);

Care must be taken to not read from the stderr after any call to process_destroy.

Waiting on a Process

To wait for a previously created process to finish executing you call process_join like so:

int process_return;
int result = process_join(&process, &process_return);
if (0 != result) {
  // an error occurred!
}

The return code of the child process is returned in the second argument (stored into process_return in the example above). This parameter can be NULL if you don't care about the process' return code.

Destroying a Process

To destroy a previously created process you call process_destroy like so:

int result = process_destroy(&process);
if (0 != result) {
  // an error occurred!
}

Note that you can destroy a process before it has completed execution - this allows you to spawn a process that would outlive the execution of the parent process for instance.

Todo

The current list of todos:

• Add the ability to set environment variables of the child process as suggested by @graphitemaster.
• Add the ability to specify if a child process should die if the parent process is terminated.

License

This is free and unencumbered software released into the public domain.

Anyone is free to copy, modify, publish, use, compile, sell, or distribute this software, either in source code form or as a compiled binary, for any purpose, commercial or non-commercial, and by any means.

In jurisdictions that recognize copyright laws, the author or authors of this software dedicate any and all copyright interest in the software to the public domain. We make this dedication for the benefit of the public at large and to the detriment of our heirs and successors. We intend this dedication to be an overt act of relinquishment in perpetuity of all present and future rights to this software under copyright law.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

For more information, please refer to http://unlicense.org/