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system(3) [freebsd man page]

SYSTEM(3)						   BSD Library Functions Manual 						 SYSTEM(3)

NAME
system -- pass a command to the shell LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdlib.h> int system(const char *string); DESCRIPTION
The system() function hands the argument string to the command interpreter sh(1). The calling process waits for the shell to finish execut- ing the command, ignoring SIGINT and SIGQUIT, and blocking SIGCHLD. If string is a NULL pointer, system() will return non-zero if the command interpreter sh(1) is available, and zero if it is not. RETURN VALUES
The system() function returns the exit status of the shell as returned by waitpid(2), or -1 if an error occurred when invoking fork(2) or waitpid(2). A return value of 127 means the execution of the shell failed. SEE ALSO
sh(1), execve(2), fork(2), waitpid(2), popen(3) STANDARDS
The system() function conforms to ISO/IEC 9899:1990 (``ISO C90'') and is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible. BSD
June 4, 1993 BSD

Check Out this Related Man Page

SYSTEM(3)						   BSD Library Functions Manual 						 SYSTEM(3)

NAME
system -- pass a command to the shell LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdlib.h> int system(const char *command); DESCRIPTION
The system() function hands the argument command to the command interpreter sh(1). The calling process waits for the shell to finish execut- ing the command, ignoring SIGINT and SIGQUIT, and blocking SIGCHLD. If command is a NULL pointer, system() will return non-zero if the command interpreter sh(1) is available, and zero if it is not. RETURN VALUES
The system() function returns the exit status of the shell as returned by waitpid(2), or -1 if an error occurred when invoking fork(2) or waitpid(2). A return value of 127 means the execution of the shell failed. SEE ALSO
sh(1), execve(2), fork(2), waitpid(2), popen(3) STANDARDS
The system() function conforms to ISO/IEC 9899:1990 (``ISO C90'') and is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible. BSD
June 4, 1993 BSD

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