fgets() crashes in coreos
I have this C code snippet which runs on a coreOS machine:
char db[512];
snprintf(db, 512, "%s %s", <some command>, <args of the command>);
FILE* pipe = popen(db, "r");
if (!pipe)
return NULL;
char buf[256];
while (fgets(buf, sizeof(buf), pipe) != NULL)
<DEBUG POINT 1>
<some code utilising buf>
<DEBUG POINT 2>
Now the command that is being executed and which is streaming to the Pipe in eventually calling a python code which returns None(Null) with the given argument.
The problem that I'm facing is that fgets is not able to handle the response and the program crashes when it tries to execute fgets() on the Pipe. What I mean is that on reaching while(), my program exits and is not able to reach either DEBUG POINT 1 or 2. I have tried searching for possible solutions but am not able to find anything.
Another interesting thing is when I run the same code on a Amazon Linux Machine, it works fine and I get the desired behaviour.
Can someone please guide me in the right direction.
c linux fgets coreos
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
add a comment |
I have this C code snippet which runs on a coreOS machine:
char db[512];
snprintf(db, 512, "%s %s", <some command>, <args of the command>);
FILE* pipe = popen(db, "r");
if (!pipe)
return NULL;
char buf[256];
while (fgets(buf, sizeof(buf), pipe) != NULL)
<DEBUG POINT 1>
<some code utilising buf>
<DEBUG POINT 2>
Now the command that is being executed and which is streaming to the Pipe in eventually calling a python code which returns None(Null) with the given argument.
The problem that I'm facing is that fgets is not able to handle the response and the program crashes when it tries to execute fgets() on the Pipe. What I mean is that on reaching while(), my program exits and is not able to reach either DEBUG POINT 1 or 2. I have tried searching for possible solutions but am not able to find anything.
Another interesting thing is when I run the same code on a Amazon Linux Machine, it works fine and I get the desired behaviour.
Can someone please guide me in the right direction.
c linux fgets coreos
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58
add a comment |
I have this C code snippet which runs on a coreOS machine:
char db[512];
snprintf(db, 512, "%s %s", <some command>, <args of the command>);
FILE* pipe = popen(db, "r");
if (!pipe)
return NULL;
char buf[256];
while (fgets(buf, sizeof(buf), pipe) != NULL)
<DEBUG POINT 1>
<some code utilising buf>
<DEBUG POINT 2>
Now the command that is being executed and which is streaming to the Pipe in eventually calling a python code which returns None(Null) with the given argument.
The problem that I'm facing is that fgets is not able to handle the response and the program crashes when it tries to execute fgets() on the Pipe. What I mean is that on reaching while(), my program exits and is not able to reach either DEBUG POINT 1 or 2. I have tried searching for possible solutions but am not able to find anything.
Another interesting thing is when I run the same code on a Amazon Linux Machine, it works fine and I get the desired behaviour.
Can someone please guide me in the right direction.
c linux fgets coreos
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
I have this C code snippet which runs on a coreOS machine:
char db[512];
snprintf(db, 512, "%s %s", <some command>, <args of the command>);
FILE* pipe = popen(db, "r");
if (!pipe)
return NULL;
char buf[256];
while (fgets(buf, sizeof(buf), pipe) != NULL)
<DEBUG POINT 1>
<some code utilising buf>
<DEBUG POINT 2>
Now the command that is being executed and which is streaming to the Pipe in eventually calling a python code which returns None(Null) with the given argument.
The problem that I'm facing is that fgets is not able to handle the response and the program crashes when it tries to execute fgets() on the Pipe. What I mean is that on reaching while(), my program exits and is not able to reach either DEBUG POINT 1 or 2. I have tried searching for possible solutions but am not able to find anything.
Another interesting thing is when I run the same code on a Amazon Linux Machine, it works fine and I get the desired behaviour.
Can someone please guide me in the right direction.
c linux fgets coreos
c linux fgets coreos
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
asked Nov 16 '18 at 6:42
Simran BindraSimran Bindra
61
61
Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58
add a comment |
Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58
Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58
Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58
add a comment |
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Are you sure the binary you run is properly built for the target platform ? If so, try running it in a debugger.
– Sander De Dycker
Nov 16 '18 at 7:58