python 2 subprocess check_output not returning error output -

i have method

def do_sh_shell_command(string_command, env_variables=none):     cmd = shlex.split(string_command)     try:        p = subprocess.check_output(string_command, shell=true,                                    env=env_variables) # shell=true means sh shell used      except subprocess.calledprocesserror e:         print 'error running command: ' + '"' + e.cmd + '"' + ' see above shell error'         print 'return code: ' + str(e.returncode)         return e.returncode, e.cmd     return 0, p 

which work reason doesn't return error output specfici command

def hold_ajf_job(job_order_id):     #print 'ctmpsm -updateajf ' + job_order_id + ' hold'     return do_sh_shell_command('ctmpsm -updateajf ' + job_order_id + ' hold')  hold_ajf_job('0e4ba') do_sh_shell_command('lsl') 

output:

ctmpsm -updateajf 0e4ba hold error running command: "ctmpsm -updateajf 0e4ba hold" see above shell error return code: 1 /bin/sh: lsl:  not found error running command: "lsl" see above shell error return code: 127 

when run command ctmpsm -updateajf 0e4ba hold form normal shell below error output

ctmtest1-tctmsv80 [288] ctmpsm -updateajf 0e4ba hold failed hold orderno 0000e4ba. (rc=jobstatincm). 

this different un-useful error output in python code , can't life of me figure out why?

update:

trying stderr=subprocess.stdout

def do_sh_shell_command(string_command, env_variables=none):     cmd = shlex.split(string_command)     try:        p = subprocess.check_output(string_command, stderr=subprocess.stdout, shell=true,                                    env=env_variables) # shell=true means sh shell used      except subprocess.calledprocesserror e:         print 'error running command: ' + '"' + e.cmd + '"' + ' see above shell error'         print 'return code: ' + str(e.returncode)         return e.returncode, e.cmd     return 0, p 

output:

error running command: "ctmpsm -updateajf 0e4ba hold" see above shell error return code: 1 error running command: "lsl" see above shell error return code: 127 

now errors have disappeared?

as documented, when check_output raises exception, places output of command in output attribute of exception object. can following:

try:     p = subprocess.check_output(string_command, stderr=subprocess.stdout,                                 shell=true, env=env_variables) except subprocess.calledprocesserror e:     print e.output     print 'error running command: ' + '"' + e.cmd + '"' + ' see above shell error'     print 'return code: ' + str(e.returncode)     return e.returncode, e.cmd return 0, p