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plurals

POdup2() and exec()
primarykey
Id
4981113
data
AcceptedAnswerId
0
AnswerCount
4
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2011-02-12T22:46:02.363
FavoriteCount
0
LastActivityDate
2014-10-02T04:27:46.800
LastEditDate
LastEditorUserId
0
OwnerUserId
614613
ParentId
0
PostTypeId
1
Score
5
ViewCount
4875
LastEditorDisplayName
text
Body
<pre><code>#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> int main( int argc, char **argv) { int pfds[ 2], i; size_t pbytrd; pid_t childpid; char buffer[ 200]; pipe( pfds); if( ( childpid = fork() ) == -1) { perror( "fork error: "); exit( 1); } else if( childpid == 0) { close( pfds[ 0]); dup2( pfds[1], 1); close( pfds[ 1]); for( i = 0; i < 10; i++) printf("Hello..."); execlp( "xterm","xterm","-e","./sample_a", (char *) 0); exit( 0); } else { close( pfds[ 1]); for( ; ; ) { if( ( pbytrd = read( pfds[ 0], buffer, sizeof( buffer) ) ) == -1) { perror(" read error: "); exit( 1); } else if( pbytrd == 0) { write( fileno( stdout), "Cannot read from pipe...\n", strlen( "Cannot read from pipe...\n") ); exit( 0); } else { write( fileno( stdout), "MESSAGE: ", strlen( "MESSAGE: ") ); write( fileno( stdout), buffer, pbytrd); } } } return( 0); </code></pre> } My sample_a.c code is below: <pre><code>#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> int main( int argc, char **argv) { int i; for( i= 0; i< 10; i++) write( fileno( stdout), "Hello...", strlen( "Hello...") ); return( 0); } </code></pre> In the above code, what I really want to do is: 1) Redirect output from the child process to pipe and have parent read from the pipe and print it out to stdout. I am able to redirect child process output( "printf") from stdout to the pipe but I am not able to redirect execlp's child process, xterm, output to the pipe. Can anybody help me this?
Tags
<c><exec><parent-child><pipe><dup2>
Title
dup2() and exec()
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. This table or related slice is empty.
UserOwnerUserId
1. USThe Champ
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
2. PO
 singulars
 PostTypePostTypeId
 PTAnswer
3. PO
 singulars
 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 POdup2() and exec()
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
2. VO
 singulars
 PostPostId
 POdup2() and exec()
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

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