[EXTERNAL] Getting return code "127" after execution of program

[Brian Inglis]

On 2023-06-02 09:07, Lavrentiev, Anton (NIH/NLM/NCBI) [C] via Cygwin wrote:
>> The Program is not throwing any error or success details. it simply comes
>> out from the running screen without any error and success states.

> 127 is a POSIX return code meaning the binary file is not executable and cannot be started.
> Check what "ldd ./sample" shows.  Most likely you are missing the required runtime (dlls).

Especially check that the DLL dependencies including cygwin1.dll are all 
installed in some .../bin/ directory which is at or near the start of your PATH, 
and that any other file dependencies are also installed under the same upper 
level Cygwin "ROOT" directory (the directory above the cygwin1.dll)!

What those file dependencies are will depend on what your program calls e.g.

$ ls -gloU /etc/{mtab,hosts,networks,protocols,services}
lrwxrwxrwx 1 12 Sep  1  2015 /etc/mtab -> /proc/mounts
lrwxrwxrwx 1 53 Sep  1  2015 /etc/hosts -> 
../proc/cygdrive/c/Windows/System32/drivers/etc/hosts
lrwxrwxrwx 1 56 Sep  1  2015 /etc/networks -> 
../proc/cygdrive/c/Windows/System32/drivers/etc/networks
lrwxrwxrwx 1 56 Sep  1  2015 /etc/protocols -> 
../proc/cygdrive/c/Windows/System32/drivers/etc/protocol
lrwxrwxrwx 1 56 Sep  1  2015 /etc/services -> 
../proc/cygdrive/c/Windows/System32/drivers/etc/services

also /etc/{fstab,fastab.d/,nsswitch}, /dev/{mqueue,shm}, 
/var/run/{cygfork/,utmp} and others.

Some may be set up by the initialization code, others by the Cygwin Setup 
program, or postinstall scripts, and may need to be set up externally if the 
Cygwin Setup program is not used, e.g. /home/, /tmp/, /usr/, /var/ if the 
program calls functions which use those.

-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry