CMake temporary directory
Creating a unique temporary directory is not completely trivial. Despite the POSIX standard, some CIs (e.g. GitHub Actions) and Unix-like operating systems (e.g. RHEL) do not define the environment variables “TMPDIR” or “TEMP” for temporary directory.
Caveat: virus scanners can false detect activity in the system temporary directory as malicious.
Create a temporary directory in CMake:
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| #include <stdio.h> | |
| int main(void){ | |
| char name[L_tmpnam]; | |
| if(tmpnam(name) == NULL){ | |
| printf("Temporary file name: %s\n", name); | |
| return 0; | |
| } | |
| return 1; | |
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| #include <cstdio> | |
| #include <iostream> | |
| int main(){ | |
| char name[L_tmpnam]; | |
| if(std::tmpnam(name)){ | |
| std::cout << "Temporary file name: " << name << std::endl; | |
| return 0; | |
| } | |
| return 1; | |
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| function(get_temp_dir ovar) | |
| find_program(mktemp NAMES mktemp) | |
| if(mktemp) | |
| execute_process(COMMAND mktemp -d OUTPUT_VARIABLE out OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE ret) | |
| if(ret EQUAL 0) | |
| set(${ovar} ${out} PARENT_SCOPE) | |
| return() | |
| endif() | |
| endif() | |
| find_program(pwsh NAMES pwsh) | |
| if(pwsh) | |
| execute_process(COMMAND pwsh -c "[System.IO.Path]::GetTempPath()" OUTPUT_VARIABLE out OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE ret) | |
| if(ret EQUAL 0) | |
| string(RANDOM LENGTH 12 _s) | |
| set(out ${out}${_s}) | |
| file(MAKE_DIRECTORY ${out}) | |
| set(${ovar} ${out} PARENT_SCOPE) | |
| return() | |
| endif() | |
| endif() | |
| message(FATAL_ERROR "Could not find mktemp or pwsh to make temporary directory") | |
| endfunction(get_temp_dir) | |
| # demo | |
| get_temp_dir(TEMPDIR) | |
| message(STATUS "temporary directory: ${TEMPDIR}") |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| function(get_temp_file ovar) | |
| find_program(mktemp NAMES mktemp) | |
| if(mktemp) | |
| execute_process(COMMAND mktemp OUTPUT_VARIABLE out OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE ret) | |
| if(ret EQUAL 0) | |
| set(${ovar} ${out} PARENT_SCOPE) | |
| return() | |
| endif() | |
| endif() | |
| find_program(pwsh NAMES pwsh) | |
| if(pwsh) | |
| execute_process(COMMAND pwsh -c "New-TemporaryFile | Select -ExpandProperty FullName" OUTPUT_VARIABLE out OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE ret) | |
| if(ret EQUAL 0) | |
| set(${ovar} ${out} PARENT_SCOPE) | |
| return() | |
| endif() | |
| endif() | |
| message(FATAL_ERROR "Could not find mktemp or pwsh to make temporary file") | |
| endfunction(get_temp_file) | |
| # demo | |
| get_temp_file(TEMPFILE) | |
| message(STATUS "temporary file: ${TEMPFILE}") |