[Bug] `g.proj` output is not flushed to stdout when redirected in Windows

[pedromxavier]

To Reproduce Steps to reproduce the behavior:

1. Run g.proj -w as a command line utility or using Python: gs.start_command + gs.communicate / gs.read_command.
2. Run the same command but redirect STDOUT to a file g.proj -w 1> proj.out.txt or using Python: gs.start_command(..., stdout=gs.PIPE).

Expected behavior When doing 1., it will output the correct projection string to the terminal. When using 2. to retrieve the string produced by the command, the proj.out.txt file (or the result from the gs.communicate call) will be empty.

System description:

• Operating System: Windows 11
• GRASS GIS version 7.8.8 (latest available through OSGeo4W)

Additional context After some investigation, I found out (from the source of g.proj) that it will print results using fprintf(stdout, ...) but will not call fflush(stdout) upon completion. This leads to a situation in Windows where the OS will flush it automatically when printing to the screen but not when the output is redirected, leading to truncated files. A simple fix would be to add a fflush(stdout) call by the end of all utilities that rely on printing to stdout.

[hellik]

tested here with

System Info                                                                     
GRASS version: 8.3.2                                                            
Code revision: exported                                                         
Build date: 2024-05-20                                                          
Build platform: x86_64-w64-mingw32                                              
GDAL: 3.9.0                                                                     
PROJ: 9.4.0                                                                     
GEOS: 3.12.1                                                                    
SQLite: 3.45.1                                                                  
Python: 3.12.4                                                                  
wxPython: 4.2.1                                                                 
Platform: Windows-11-10.0.22631-SP0 (OSGeo4W)       

and

GRASS version: 8.5.0dev                                                         
Code revision: 0b0cffce0                                                        
Build date: 2024-06-16                                                          
Build platform: x86_64-w64-mingw32                                              
GDAL: 3.9.0                                                                     
PROJ: 9.4.0                                                                     
GEOS: 3.12.2                                                                    
SQLite: 3.45.1                                                                  
Python: 3.12.4                                                                  
wxPython: 4.2.1                                                                 
Platform: Windows-11-10.0.22631-SP0 (OSGeo4W)  

g.proj -w 1> proj.out.txt and g.proj -w > proj.out.txt work on the OSGeo4W command shell